KAYAK Team

Steve Hafner, Chief Executive Officer and cofounder

Steve Hafner is Chief Executive Officer and cofounder. When starting KAYAK, Steve brought extensive knowledge about e-commerce, online travel, and marketing to KAYAK. He helped found Orbitz, the online travel agency, in November 1999 and led their business development, advertising sales, marketing, and product marketing activities. Steve is very involved in every commercial aspect of KAYAK as well as product development.

Before 1999, Steve worked as a strategy consultant at the Boston Consulting Group. He began his career at Marketing Corporation of America that was later acquired by Interpublic Group. Steve received a BA in Economics from Dartmouth College and an MBA from the Kellogg Graduate School of Management at Northwestern University.

Paul English, Chief Technology Officer and cofounder

Paul English is Chief Technology Officer and cofounder. Before starting KAYAK, Paul was a lifelong technology entrepreneur. He co-founded Boston Light Software, a small business e-commerce platform that was sold to Intuit. At Intuit, Paul became Vice President of technology and led small business Internet and product strategy, company-wide innovation process, and tech recruiting.

Paul was briefly an entrepreneur in-residence at Greylock, a co-founder and Director of Intermute, the founder of the World Xiangqi League, cofounder and Chairman of Mancala, Inc., Senior Vice President of Engineering and Product Management at Interleaf. He also did contract programming for the US Air Force, operations research programming for Data General, programming for a medical device company, and even some video game software and sound-effect development.

Paul is involved in nearly every aspect of our company, but he spends most of his time leading product strategy and design, customer support and recruiting. Paul is obsessed with customer feedback. (He hates bad customer service so much that he launched the www.gethuman.com initiative to help consumers fight back against bad phone systems.)

Paul received a BS and MS in computer science from University of Massachusetts. Paul regularly lectures on entrepreneurship topics at Boston-area universities, and was named Chief Technology Officer of the year by Mass Technology Leadership Council in 2009. He's also a Director at Partners-In-Health and Village Health Works, and is an advisor to JoinAfrica, FanSnap, Roost, LinkedIn, and Pixable.

Bill Smith, Chief Financial Officer

As Chief Financial Officer, Bill Smith oversees the company’s worldwide financial operations and strategy. Bill also serves as the primary executive manager to the Audit Committee of the Board of Directors, and leads the company’s risk management policies.

Bill leads the development, implementation and communication of the company’s financial strategy and business model development including executing M&A initiatives.

Bill brought significant finance operations and capital markets experience to KAYAK. He previously held a variety of finance-related positions with Novell, Inc., most recently as Vice President, Global Finance. His previous experience includes financial advisory services at Cowen & Co. and Morgan Stanley.

Bill received a BA in history from Dartmouth College and an MBA from The Wharton School, University of Pennsylvania.

Paul Schwenk, Senior Vice President of Engineering

As Senior Vice President of Engineering, Paul leads the day-to-day product development and operational efforts for the company. Paul has been with the company since it was founded in 2004.

Before KAYAK, Paul was a senior engineer at Boston Light Software, a small business e-commerce platform that was sold to Intuit. At Intuit, Paul became a Senior Group Manager within the Small Business Division. Paul’s previous technology experience includes co-founding Digital Direct Network, a multi-media networking startup and engineering roles at Avid and Interleaf.

Paul received a BS in computer science from Rochester Institute of Technology.

Robert Birge, Chief Marketing Officer

As Chief Marketing Officer, Robert Birge leads the company’s efforts to grow the number of people who use KAYAK and to build the KAYAK brand. He also manages corporate communications and supports the product development team.

Robert spent the past 18 years working in a breadth of marketing roles including overseeing marketing during the start-up phase of Orbitz while a consultant at the Boston Consulting Group. Prior to joining KAYAK, Robert served as global Chief Marketing Officer of sports and entertainment company, IMG. He also worked at global advertising agency TBWA\Chiat\Day as Managing Director of the New York office and at Miller Brewing Company in brand management.

Robert received a BA in History from Dartmouth College and an MBA from the Kellogg Graduate School of Management at Northwestern University.

Keith Melnick, Chief Commercial Officer

As Chief Commercial Officer, Keith Melnick oversees revenue-generating activity at KAYAK, including managing distribution agreements with distribution partners and advertising sales. Keith has been with the company since it was founded in 2004.

Keith brings nearly a decade of travel industry experience in strategy, business development, and revenue management. Prior to joining KAYAK, Keith was a management consultant at the Boston Consulting Group where he managed case teams for travel, e-commerce, and financial services clients. During his time at the Boston Consulting Group (BCG), Keith helped found online travel agency Orbitz. Prior to BCG, Keith worked in Revenue Management and Finance at American Airlines.

Keith received a BS in Mechanical Engineering from the University of Illinois and an MBA in Finance with highest honors from the University of Southern California.

Karen Klein, General Counsel

As General Counsel, Karen Klein provides legal counsel to senior management and oversight of all legal matters.

Prior to joining KAYAK, Karen spent over six years with Orbitz, where she held a variety of positions in the legal department, most recently as Group Vice President, Legal. Prior to Orbitz, Karen served as legal counsel at several software companies, including as General Counsel and Corporate Secretary for Installshield Software Corporation and Assistant General Counsel for Platinum Technology International, Inc. Karen began her legal career in 1995 as an associate at Katten Muchin Rosenman.

Karen graduated from the University of Wisconsin and graduated with Highest Honors from Chicago-Kent College of Law, where she was a member of the Law Review and Order of the Coif.

Melissa Reiter, SVP, Finance and Investor Relations

As Senior Vice President of Finance and Investor Relations Melissa Reiter manages the company’s global finance and accounting teams, and manages the company’s relationships with with the investment community.

Prior to joining KAYAK, she held various financial leadership roles including Vice President of Finance at Potbelly Sandwich Works and Controller at Orbitz Worldwide.

She started her career in the audit practice of Arthur Andersen where she was a senior manager. Melissa received a BS in Business Administration from Miami University and is a Certified Public Accountant.

Christian Saller, Managing Director, KAYAK Europe

As Managing Director KAYAK Europe, Christian Saller oversees the European operations of KAYAK.

Christian spent the past 8 years working with growth companies in the digital media space. Prior to joining KAYAK, he was Chief Executive Officer of swoodoo AG, the leading German travel search site, which KAYAK acquired in 2010. He also worked as Chief Financial Officer at GIGA Digital Television, a German media company, as investment manager at venture capital firm Target Partners, and as a consultant at Monitor Group.

Christian holds a Masters and PhD in Mathematics from Munich Technical University (TU München) and an MBA from London Business School, all with distinction.

Bill O'Donnell, Chief Architect and General Manager, KAYAK Mobile

As Chief Architect and General Manager of KAYAK Mobile, Bill O’Donnell oversees overall technical design of the website and the development and strategy for KAYAK’s mobile applications. Bill has been with the company since it was founded in 2004.

Bill has been a professional programmer for over 20 years. Before joining KAYAK, Bill was Chief Architect for the shared product components group at Intuit, Inc. Bill’s experience also includes software development at Interleaf where he invented and wrote Cyberleaf, one of the first large scale document publishing systems for the World Wide Web.

Bill graduated with an BS in electrical engineering from Carnegie Mellon University.

Giorgos Zacharia, Chief Scientist

As Chief Scientist, Giorgos Zacharia oversees technology strategy and intellectual property portfolio management at KAYAK. He also manages our algorithms, personalization, search speed, and result optimizations.

Before KAYAK, Giorgos was the Founder, Chief Technology Officer, and Chief Scientist of Open Ratings Inc. (ORI). At ORI, he led the development of supply base risk management solutions using predictive data mining, leading to the invention of the most accurate corporate bankruptcy analytics algorithms. Giorgos has also helped found several other technology companies including two machine learning-driven hedge funds, Stocknomics Ltd., and Emporics Capital Management, and Kypros-Net, Inc., a portal on Cyprus, with a collaborative community for learning Modern Greek.

Giorgos holds a PhD in Computer Science, and three more degrees in Mathematics and Computer Science from the Massachusetts Institute of Technology, where he was a Fulbright Scholar, and Telecom Italia Fellow. Giorgos has won five medals in International Mathematical and Physics Olympiads, and before MIT, he served as an artillery Sergeant in the Cyprus National Guard, commanding a surface-to-air missile system squad.