Accessing our ecosystem.
The average tenure within our leadership team is 20 years. For employees overall it is 10. We believe that says a lot about who we are and how we work. The vast Zell network of companies and alumni provides us — and our portfolio companies — with an advantage in accessing resources and opportunity.
Sam Zell is a global, industry-agnostic entrepreneur and investor. He has a long track record of turning around troubled companies and assets, leading industry consolidations, and bringing companies to the public markets. His current investments are in: energy, logistics, manufacturing, communications, healthcare, and real estate.
Sam is the Chairman of Equity Group Investments, the private investment firm he founded more than 45 years ago. He also chairs five companies listed on the New York Stock Exchange: Equity Residential, the largest apartment REIT in the country; Equity LifeStyle Properties, a manufactured home community and resort REIT; Equity Commonwealth, an office REIT; Covanta Holding Corporation, an international owner/operator of energy-from-waste and power generation facilities; and Anixter International Inc., a leading global provider of communications, security, and wire and cable products.
Sam also founded and chaired Equity Office Properties Trust, the largest office REIT until its 2007 sale for $39 billion in the largest leveraged buyout at the time. In addition, he introduced the first Brazilian and Mexican real estate companies, respectively, to the New York Stock Exchange through Equity International, a second private investment firm he founded to focus on real estate-related businesses in emerging markets.
Sam is an active philanthropist with a focus on entrepreneurial education. Through the Zell Family Foundation, he has led the sponsorship of several leading entrepreneurship programs, including: the Zell/Lurie Institute for Entrepreneurial Studies at University of Michigan’s Ross School of Business; the Zell Fellows Program at Northwestern University’s Kellogg School of Management; and the Zell Entrepreneurship Center at the Interdisciplinary Center Herzliya (IDC). The Zell Global Entrepreneur Network (ZGEN) unites the students and alumni of these programs and actively provides them with connections, opportunities, mentorship and support. Sam also sponsors the Samuel Zell/Robert Lurie Real Estate Center at University of Pennsylvania’s Wharton Real Estate Center. He holds a JD degree and a BA from the University of Michigan.
Sam was recognized in 2017 by Forbes as one of the 100 Greatest Living Business Minds. Also in 2017, Sam debuted his book, Am I Being Too Subtle? (Penguin RandomHouse), in which he shares fundamentals and philosophies that made him a self-made billionaire.
As Co-President of EGI, David Helfand is involved with all aspects of the firm with a focus on EGI’s real estate activities. He has worked with Sam Zell for more than 28 years in a variety of capacities. David also serves as President and Chief Executive Officer of Equity Commonwealth (EQC), and is a member of the company’s board of directors. EQC is an internally managed and self-advised REIT. Prior to re-joining EGI in 2011, David was Founder and President of Helix Funds, where he oversaw the acquisition, management, and disposition of more than $2.2 billion in real estate assets. While at Helix, David also served as Chief Executive Officer for American Residential Communities, a Helix portfolio company.
Before founding Helix, David served as Executive Vice President and Chief Investment Officer for Equity Office Properties Trust, the largest REIT in the U.S. at the time, where he led approximately $12 billion of mergers and acquisitions activity. Prior to Equity Office, David served as a Managing Director and participated in the formation of Equity International, a private investment firm focused on building real estate-related businesses in international emerging markets. He also held the role of President and Chief Executive Officer of Equity LifeStyle Properties, Inc., a manufactured home community and resort REIT, and served as Chairman of the board’s audit committee. His earlier career included investment activity in a variety of asset classes, including retail, office, parking, and multifamily.
He holds an MBA from the University of Chicago Graduate School of Business, and a BA from Northwestern University. David serves as a Director on the boards of the Ann & Robert H. Lurie Children’s Hospital of Chicago and The Ounce of Prevention, and as a Commissioner for the Chicago Park District. He is also on the Executive Committee of the Zell/Lurie Real Estate Center at The Wharton School, and the Board of Visitors at the Weinberg College of Arts and Sciences at Northwestern University.
As Co-President, Mark oversees all aspects of EGI. He focuses on maximizing and sustaining the value of the firm’s investment portfolio, and on optimizing Sam’s vast network. With nearly 20 years of board and CEO experience, Mark employs his leadership inside and outside our firm. He manages and develops our corporate investment team, and deploys Sam’s active-ownership approach by engaging with portfolio company management to improve business strategies and operating structures, aligning all toward achieving optimum shareholder value. In addition, Mark is a Senior Managing Director of Chai Trust Company, LLC (corporate trustee for the Zell family trusts). He serves EGI investments as Executive Chairman on the board of directors of Exterran Corporation, a global market leader in natural gas production and processing services; and he is on the boards of SIRVA, Inc., a provider of moving and relocation services, and Ardent Health Partners, LLC, a provider of hospital and healthcare services.
Mark joined EGI in 2006 as a Managing Director. He has overseen a range of investments, serving in the ownership representative role of strategic advisor to portfolio company management teams. Mark has served on temporary in-house assignments within select EGI portfolio companies to accelerate and increase the effectiveness of turnarounds. He performed this role as President of Tribune Interactive from 2007 to 2008, and again more recently within Exterran Holdings, Inc.
Before joining EGI, Mark was the Chief Executive Officer of Sunburst Technology Corporation and served on the company’s board of directors. Previously, he was the President of Budget Group, Inc. (Budget Rent A Car and Ryder Truck Rental), and served on that company’s board as well. Mark’s earlier career also included senior brand management and sales roles at The Coca-Cola Company. He holds an MBA from Harvard Business School and a BA from Amherst College. Outside of the office, Mark invests time mentoring young parents of children with special needs.
Chief Financial Officer, Chief Operating Officer
As CFO, Philip works closely with the investment team to structure transactions, assist in financial due diligence, and facilitate bank discussions. Internally, he oversees the financial services group, which houses EGI’s accounting, treasury, and tax functions. He also serves as COO, managing the firm’s human resources, administration, and facilities functions. Philip is also CFO of Chai Trust Company, LLC (corporate trustee for the Zell family trusts). Since 1990, he has served in various leadership capacities for EGI and its affiliates. Among those roles was CFO of Danielson Holding Corporation, the predecessor of Covanta Holding Corporation, an international owner/operator of energy-from-waste and power generation facilities. Earlier in his career, Philip served as the CEO and CFO of First Capital Financial, LLC, and as the Managing General Partner of the First Capital real estate funds. He began his career at Ernst & Young. Philip holds an MST from DePaul University and a BS from Northern Illinois University.
Chief Legal Officer and Managing Director
Jon oversees all of EGI’s legal activities. He works with the investment team and outside counsel on transactions, disputes and other matters, and is on the boards of a number of companies in which EGI owns an interest. Jon is also a Senior Managing Director of Chai Trust Company, LLC (corporate trustee for the Zell family trusts), is personal legal advisor to Sam Zell, and works with the Zell family and the Zell Family Foundation on philanthropic and other matters. Prior to rejoining EGI in 2009, he was a partner at Neal, Gerber & Eisenberg in the Corporate and Securities, Private Wealth Services and Life Sciences practice groups. Earlier in his career, Jon served as an attorney at EGI affiliate Rosenberg & Liebentritt, as general counsel of AlliedSignal’s safety restraints business, and as an Associate at Skadden, Arps, Slate, Meagher & Flom. He holds a JD degree from University of Chicago Law School and a BA with highest honors and comprehensive honors from University of California at Santa Cruz. Jon is a member of the board of directors of Illinois Legal Aid Online.
In 1994, responding to a signal from planet Zell to bring an alien approach to corporate operations, Bill realized an opportunity to both serve and evolve purpose. He creates budgets; procures animals, vegetables, minerals, and humans; and manages the process and the people for a wide array of marketing and advertising projects – all the while dissolving existing and imagined barriers between the creative and reality.
Vice President - Tax
Jim contributes his tax expertise in all related areas at EGI, including planning and structuring business transactions. He has been with us and our affiliated companies since 1981. Prior to joining EGI, Jim worked for the international accounting firms of Touche Ross and JK Lasser. He holds a BS in Accounting from Northern Illinois University and is a Certified Public Accountant.
Managing Director - Investments
Peter has more than 30 years of experience in growing companies on institutional and entrepreneurial platforms. He focuses on evaluating new investments and monitoring portfolio assets. Peter serves on the boards of several EGI portfolio companies. He is Chairman of Ardent Health Partners, LLC, a provider of hospital and healthcare services, and Chairman of Veridiam, Inc., a specialty alloy manufacturer serving the nuclear power, medical, aerospace and automotive markets. Peter also serves on the board of Covanta Holding Corporation, an international owner/operator of energy-from-waste and power generation facilities. He is also an active board member for: Frontier Communications Corporation, Goodman Theatre, Rush University Medical Center, and The CORE Center for the Research and Cure of Infectious Diseases.
Prior to joining EGI in 2014, Peter served as Chief Executive Officer of Rewards Network, Inc., a dining rewards company; and as a partner and Chief Operating Officer at Loop Capital Markets, a full-service investment bank/broker dealer. Earlier in his career, Peter was a Senior Partner at DLA Piper US LLP. He has also served as Chairman of the Chicago Plan Commission, the Chicago Landmarks Commission, and the Illinois Sports Facilities Authority, and as a director of Rewards Network, Inc., Jacor Communications, and Blue Chip Broadcasting. Peter was the Managing General Partner of the NBA’s Denver Nuggets from 1989-1992.
Peter earned his JD degree from Harvard Law School and his MBA from the Harvard School of Graduate Management Education. He graduated cum laude from Harvard College. He is a member of the Illinois Bar and a registered real estate broker.
Tyler evaluates potential new investments and monitors existing EGI assets, including Ardent Health Partners, LLC, a provider of hospital and healthcare services. Prior to joining EGI in 2018, he served as a private equity associate with the Silverfern Group, where he evaluated investment opportunities across the financial services, consumer and energy sectors, monitored portfolio company performance, and developed valuations. Tyler also served as an investment banking analyst at Oppenheimer & Co., Inc. as a member of the firm’s consumer investment banking team, where he focused on executing mergers & acquisitions and equity financings for middle market and lower middle market clients. Tyler holds a BA in economics with honors from Johns Hopkins University.
Evan sources and evaluates credit and equity investment opportunities in the public and private sectors, negotiates and structures transactions, and partners with portfolio company operators to drive value. He is also responsible for market facing and trading activities at EGI. He serves on the boards of a number of EGI portfolio companies, including: EagleRidge Energy, LLC, an oil and gas development and production company; The Pasha Group, a provider of ocean transportation and logistics services; Ventana Exploration and Production LLC, an oil and gas acquisition and development company; and Veridiam, Inc., a specialty alloy manufacturer serving the nuclear power, medical, aerospace and automotive markets. He also oversees our investment in Waste Industries, a vertically integrated, solid waste management company, and in Penn Virginia Corporation, an oil and gas exploration, development, and production company. Prior to joining EGI in 2010, Evan served as an Associate at Trust Company of the West, where he focused on special situation investing, primarily in distressed debt and restructurings. Earlier, he was an investment banking analyst in the Leveraged Finance group at Citigroup where he was involved in a variety of debt capital-raising transactions, including leveraged buyouts, corporate-to-corporate acquisitions and other debt financing activities. He received a BBA from the Goizueta Business School at Emory University where he graduated magna cum laude and was elected to Beta Gamma Sigma.
Managing Director, Equity Group Investments
Ellen has worked in a variety of capacities for Sam’s affiliated companies since 1990. She represents EGI in sourcing potential transactions and meeting new capital sources. Ellen also serves on the board of EGI’s portfolio company SIRVA, Inc., a provider of moving and relocation services. In addition, she is responsible for establishing and overseeing the Zell Global Entrepreneurship Network (ZGEN), an organization designed to provide continuing education and mentorship for students and alumni of Sam’s three entrepreneurship education programs. During her tenure within Sam’s network, she served on the boards of Rewards Network, Inc., a dining rewards company; WRS Holding Company, an environmental construction and remediation company; East Mediterranean Gas Company SAE, an Egyptian natural gas transmission company; National Patent Development Corporation, a holding company focused on pharmaceutical and home improvement products; and Home Products International, a global consumer products company. She also held the roles of Executive Vice President at Equity International and Vice President of Scott Sports Group, Inc. Prior to joining Sam’s organization, Ellen was a financial analyst with The First Boston Corporation in New York City. She graduated magna cum laude with a BA from Harvard College, and earned her Master of Divinity from the University of Chicago in 2016.
John oversees a large alternative investment portfolio of private equity and hedge funds for EGI. He also serves as President and founder of Servant Financial, Ltd., a registered investment advisor. John is a CPA with a varied and extensive finance background. Prior to joining EGI in 2005, he served as CFO for CNA Surety, and Controller of Capsure Holdings, two NYSE-listed insurance companies. He also worked for Deloitte & Touche as senior audit manager. John graduated magna cum laude with a BS in accounting from the University of Illinois.
Vice President - Communications
Terry is responsible for EGI’s communications. Her emphasis is in strategic planning, M&A, investor communications, employee communications, crisis communications, media relations, public affairs, and board relations. Prior to joining EGI in 2007, Terry was Vice President of public relations at Equity Office Properties Trust, where she originated and managed a comprehensive, strategic external communications function for the company that included IR, PR, and public affairs. Earlier in her career, she served as Vice President of DGPR, a boutique public relations agency serving business-to-business accounts, primarily in the finance, real estate, and travel industries. Terry formerly served on the board of directors for the Chicago Children’s Advocacy Center, and is currently on the organization’s Advisory Board. She holds a BA in journalism from San Diego State University.
Michael evaluates potential new investments and works directly with existing assets. He serves on the board of directors of EGI portfolio company Crystal Equity Energy, LLC, a non-operated Bakken oil and gas producer. He also supports our investments in: Anixter International, a global communications product company; Covanta Holding Corporation, an international owner/operator of energy-from-waste and power generation facilities; and The Pasha Group, a provider of ocean transportation and logistics services. Prior to joining EGI in 2016, Michael worked as an investment analyst at Hancock Capital Management, LLC in Boston, Massachusetts, where he focused on middle-market mezzanine and private equity investments. He graduated magna cum laude with a BA in economics from Boston College.
Alicja is responsible for all tax matters related to EGI investments, and oversees tax reporting. Prior to joining EGI in 2013, Alicja was Director/Vice President at Diversified Financial Management Corp., Tax Manager at Deloitte, and Experienced Senior Tax Consultant at Andersen. Alicja holds an MBA in Finance, Economics, and International Business from the University of Chicago Booth School of Business, and a BS in Accounting from the University of Illinois at Chicago. She is a Certified Public Accountant.
Nils evaluates possible new investments and monitors existing assets. He serves on the boards of two EGI portfolio companies: JL Radio, which operates a Philadelphia radio station, and Rewards Network, Inc., a dining rewards company. He rejoined EGI in 2013 from Tribune Company, where he served as Executive Vice President – Chief Investment Officer, and Co-President of Tribune Company; and as President/CEO of Tribune Broadcasting. Prior to joining Tribune in 2008, Nils served as a Managing Director of EGI, where he focused on a wide range of industries and financial securities with particular focus on the transportation, energy, media, and retail industries, and distressed debt securities. He originally joined EGI in 1995. Previously, Nils worked as a financial analyst with CS First Boston in the taxable fixed-income/derivative products group where he was involved in raising capital for international issuers and domestic financial institutions. Nils graduated summa cum laude from Bowdoin College with a BA in economics and history.
Vice President and Controller
Lucy oversees all of EGI’s accounting functions: investment accounting, fund reporting, financial reporting, real estate, and treasury. She takes a lead role in the state regulatory process, including interacting with internal and state auditors. She also oversees the company’s human resource and administrative functions. Prior to joining EGI in 2001, Lucy worked in public accounting for more than 10 years at a small local CPA firm; five of those years were spent as a partner. She is a Certified Public Accountant, and graduated with a BS from Rockford College.
Joe focuses on new investment activity, including sourcing, evaluating, and executing transactions. He also monitors existing investments. In addition, Joe serves on the boards of EGI investment Real Industry, Inc., a diversified holding company, and ILTA Grain, a leading originator, processor and exporter of pulse crops from Canada. Prior to joining EGI in 2017, he spent over 20 years as an investment banker and worked closely with the EGI team on a number of important investments and transactions including Anixter International Inc., Adams Respiratory Therapeutics, American Commercial Lines, and Penford Products. Joe was most recently at Deutsche Bank as Vice Chairman of Consumer and Retail Investment Banking Coverage, and prior to that at Bank of America as a Managing Director in the Corporate and Investment Banking division. Over the course of his investment banking career, Joe worked on a number of high-profile client transactions including: spin-off of Hanesbrands from Sara Lee; IPO of Caribou Coffee; acquisition of Ralcorp by ConAgra; spin-off of Beam Global from Fortune Brands; sale of Sara Lee’s fresh bread business to Bimbo; and many others. Joe received a JD from Northwestern University School of Law and a BBA in Accounting with Highest Distinction from the University of Iowa.
Associate General Counsel
Joe works on all of the legal aspects of EGI, including our investment portfolio and a broad range of business and operational matters. He has extensive experience in mergers and acquisitions, corporate restructurings, joint ventures and securities and corporate finance – across industries and for Fortune 50, middle-market as well as emerging companies. Prior to joining EGI in 2017, Joe worked at Skadden, Arps in the Corporate practice group. Earlier in his career, he was a manager in the consulting division of Arthur Andersen and in the legal and regulatory division of the Chicago Mercantile Exchange. He holds a JD summa cum laude from Chicago-Kent College of Law, an MBA with distinction in finance from DePaul University and a BA in finance from Michigan State University. Joe is a CPA, and a long-standing volunteer and advisor to the Chicago Lawyers’ Committee and the Community Law Project.
Chris evaluates new investment opportunities and manages existing assets. He serves on the boards of two EGI portfolio companies, Ardent Health Partners, LLC, a provider of hospital and healthcare services, and Crystal Equity Energy, LLC, a non-operated Bakken oil and gas producer. He also oversees our investments in Par Pacific Holdings, Inc., an owner and operator of energy and infrastructure business, and Dairy Farms NZ Limited, an owner of dairy farmland in New Zealand. Prior to joining EGI in 2010, Chris served as an Associate at The Circumference Group, and worked on a variety of investing and consulting opportunities. He also served as an investment banking analyst in the Leveraged Finance group at Bank of America where he was involved in a variety of capital market transactions including leveraged buyouts, corporate-to-corporate acquisitions, balance sheet restructurings and other debt financing activities. Chris graduated magna cum laude from Wake Forest University with a BS in Finance.
Rahul sources and evaluates new credit and equity investment opportunities, and works with existing investments to maximize their value. He serves on the board of EGI portfolio company Veridiam, Inc., a specialty alloy manufacturer serving the nuclear power, medical, aerospace, and industrial markets. Rahul also supports EGI’s investments in: EagleRidge Energy, LLC, an oil and gas development and production company; Ventana Exploration and Production LLC, an oil and gas acquisition and development company; Kuwait Energy Company, an international oil and gas development and production company; and Cross Border Xpress, a bi-national airport terminal that connects San Diego directly to the Tijuana Airport. Prior to joining EGI in 2015, Rahul worked as a private equity associate at BTC Partners, a search fund focused on the lower middle market, and as a senior consultant in the strategy and analytics practice at IBM. He also worked at Home Trust Company where he helped with the strategy for the launch of a new direct-to-consumer retail banking deposits business known as Oaken Financial, and at OneClass, a venture-backed startup, and provided strategic consulting to technology startups based out of Google’s Communitech Hub. He graduated with an Honors BBA from Wilfrid Laurier University.
Rob focuses on evaluating possible new investments and monitoring existing investments. He joined EGI in 2014 with more than 25 years of senior leadership experience in the private and public sectors. He serves on the boards of two EGI investments, Covanta Holding Corporation, an international owner/operator of energy-from-waste and power generation facilities; and Par Pacific Holdings, Inc., an oil and gas exploration and production company. Rob also currently serves as Executive Chairman of Strayer Education, Inc. He previously served the company in various leadership roles, including Chief Executive Officer. Rob also served in a variety of senior management positions, including President and Chief Operating Officer, at CalEnergy Company, Inc. Earlier in his career, he was Assistant to the Chairman and Chief Executive Officer of International Paper Company. He also served in several senior positions in the U.S. Department of Defense, including Assistant Secretary of the Army. Rob serves on the board of 21st Century Fox, and is a member of the Council on Foreign Relations. He holds a masters in international policy from The Johns Hopkins University, and a BA in history from Dartmouth College.
Kathleen is responsible for transaction sourcing, investment and disposition decisions, portfolio monitoring, and trading activities. She serves on the boards of two EGI portfolio companies, GreyCastle Holdings Ltd., a life reinsurance company, and Wapiti Oil and Gas, LLC, an oil and gas exploration and production company. Kathleen is also the Portfolio Manager for the Zell Credit Opportunities Fund (ZCOF), a fund focused on recapitalizing over-leveraged companies. In that role, she oversees all aspects of the fund’s investment, monetization, and reporting activities. Prior to joining EGI in 2000, Kathleen served as a financial analyst at Merrill Lynch where she focused on the automotive and heavy-industrial sectors. Kathleen serves on the Leadership Council of A Better Chicago, a venture philanthropy fund focused on improving educational opportunities for low-income students in Chicago. She graduated Phi Beta Kappa from Dartmouth College where she received an AB in Economics and Mathematics, magna cum laude.
Jay evaluates potential new investments and monitors existing assets. Specifically, he supports EGI investments in Ardent Health Partners, LLC, a provider of hospital and healthcare services, and Waste Industries, a vertically integrated, solid waste management company. Prior to joining EGI in 2015, Jay worked as an investment banking analyst in the Leveraged Finance group at Bank of America Merrill Lynch where he was involved in a variety of capital market transactions, including leveraged buyouts and corporate-to-corporate acquisitions. He graduated summa cum laude from Vanderbilt University with a BA in Economics and Mathematics.
Advisor – Real Estate
David focuses on real estate and real estate-related industries at EGI. He also serves as Executive Vice President and Chief Operating Officer of Equity Commonwealth, an internally managed and self-advised REIT. Prior to joining EGI in 2012, David served as a Principal with Helix Funds, a private real estate investment management company which acquired, managed, and disposed of over $2.2 billion in real estate. At Helix, David was responsible for investments in the multifamily and office sectors, and oversaw the firm’s dispositions for American Residential Communities, a Helix portfolio company. David also served as Vice President of investments and asset management at Equity Office Properties Trust, the largest real estate investment trust in the U.S. at the time. In this role, he participated in over $6 billion of investment activity, and oversaw Equity Office’s 16 million-square-foot portfolio in Southern California. Earlier in his career, David was Vice President of acquisitions at LaSalle Investment Management, and an attorney at the law firm of Sidley & Austin. David holds a JD degree cum laude from Northwestern University School of Law and graduated with highest honors with a BS from the University of Illinois.
Jon manages existing real estate assets, and evaluates new investment opportunities across all sectors and levels of the capital structure. Prior to joining EGI, he served as Director of Investments at Equity Commonwealth where he focused on underwriting new acquisitions and on dispositions of the firm’s non-core real estate assets. Earlier in his career, Jon served as an associate at Square Mile Capital Management and as an investment banking analyst at Deutsche Bank. He holds a BBA in Real Estate and Finance from the University of Wisconsin.
Alex evaluates potential new investments and monitors existing assets. Specifically, he serves on the board of WBEB-FM Radio, a local Philadelphia radio station company. Alex also supports EGI’s investments in: Par Pacific Holdings, Inc., owner and operator of energy and infrastructure business; GreyCastle Holdings Ltd., a life reinsurance company; and ILTA Grain, a leading originator, processor and exporter of pulse crops from Canada. Prior to joining EGI in 2016, Alex worked as an investment banking associate at Goldman Sachs in the Leveraged Finance and Natural Resources groups. He graduated summa cum laude with a BS in Economics from The Wharton School at University of Pennsylvania.
Zach manages existing real estate assets, and evaluates new investment opportunities across all sectors and levels of the capital structure. Prior to joining EGI in 2018, he served as a Senior Associate at Equity Commonwealth where he oversaw a portfolio of assets in the West, Southwest and Mid-Atlantic regions. Zach also executed dispositions of non-core assets and underwrote new investments. Earlier in his career, Zach was a Senior Associate at CBRE in Newport Beach, CA. Zach holds an MBA from the University of Wisconsin and a BA from the University of California, San Diego.
Aaron sources and evaluates potential new investments and works directly with existing assets. Specifically, he supports EGI’s investments in Exterran Corporation, a global market leader in natural gas production and processing services; The Pasha Group, a provider of ocean transportation and logistics services; and SIRVA, Inc., a provider of moving and relocation services. Prior to joining EGI in 2017, he served as a summer intern with us in 2014 and 2015. While at university he also served as an active volunteer in on-campus community organizations. Aaron graduated summa cum laude with a BS in Science of Economics from The Wharton School at the University of Pennsylvania.