Graeme Smith, Chief Executive Officer

Graeme is the CEO of Sizmek by Amazon, where he is focused on guiding the company and its leadership team and accelerating the growth of the business. Graeme joined as COO following Amazon’s acquisition of the Sizmek Ad Server and Sizmek DCO. He brings over 13 years of experience at Amazon, where he has led product, engineering and science teams, and grown their Edinburgh Development Centre. Over the past 8 years, Graeme and his teams have invented and worked with many of Amazon Advertising’s products and technologies. In his spare time, Graeme can be found running the Scottish Highlands and swimming in lochs.

Sascha Wittler, Chief Financial Officer

CFO Sascha Wittler uses his global knowledge of accounting, financial planning and analysis, M&A, and corporate strategy to help ensure Sizmek’s success. Sascha honed his financial acumen most recently as a Chief Financial Officer at ProSiebenSat.1 Group; Worldwide GroupM Connect, GroupM’s worldwide consolidated digital agency platform; and Quisma GmbH. When he’s not overseeing Sizmek’s financial future or spending time with his wife and two kids, Sascha swims, cycles, and runs, always keeping his eye on the next triathlon, or you know, “just” a marathon, to take on.

Elizabeth Christensen, Head of Global Customer Operations

As Head of Global Customer Operations, Elizabeth’s focus is wowing our customers with efficiency, accountability and world class service. She brings experience working in global roles across operations, product, sales, marketing and client service at various companies, including Eyeota, Xaxis, JWT, Team One, Sterling Publishing and more. If you can’t find Elizabeth on video conference with her global team, you will find her spending time with her family, running in the park, reading or enjoying local restaurants in Brooklyn, NY.

Samira Ebel, Head of Human Resources

People and Organization are the heart of Samira’s work, driving the talent agenda to set up Sizmek by Amazon for the future. She brings 10 years of experience as an HR Business Partner in the sectors of FCMG, technology, advertising. When Samira is not in the office, she likes to spend her time enjoying Berlin with her family.

Mark Tannen, General Manager, Americas

As GM of Americas for Sizmek by Amazon, Mark Tannen focuses on partnerships and customer strategy. In his six years at Amazon, Mark worked on the launch of the self-service DSP. Additionally, he worked in product management for Amazon’s Sponsored Ads organization, before moving into a role leading CPG sales for US and global clients for Sponsored Ads. Prior to Amazon, Mark was a consultant at IBM, and a Venture Fellow at the Zell Lurie Institute where he served as an advisor to startups. Outside of the office, Mark is a recovering ski bum (9 surgeries and counting!).

Paul Wright, General Manager, EMEA

Paul Wright’s experience as a corporate leader, technology lead, client, agency person, strategist, consultant, entrepreneur, and board advisor brings a uniquely rounded approach to the Sizmek leadership team. Prior to joining, Paul held a wide range of roles, including CEO of iotec, a demand-side platform, Director of EMEIA and APAC iAd, Apple’s digital advertising platform, and Chief Digital Officer at Omnicom Media Group, UK. Paul was also recently shortlisted for Diversity Leader of the Year by Information Age and is a trained mentor.

Peter Hunter, General Manager, APAC

Partnerships, strategic planning, and innovation—Peter Hunter bases everything he does around these objectives in his role as Sizmek General Manager, APAC. Prior to Sizmek, Peter expanded Eyeota’s product line and capabilities for ANZ as General Manager, and held senior roles at Quantcast, PHD, Inlink Media, and Dentsu Aegis’s iProspect. Raised on a farm in New Zealand where he rode a horse to school each day, Peter traded in his saddle for a steering wheel, which he uses to compete in the Sim Racing world.

Volker Hatz, Chief Product Officer

As Chief Product Officer, Volker Hatz oversees Sizmek’s fast-growing data business, including data governance solutions and analytics initiatives, and product marketing. Prior to joining Sizmek, Volker was Global Head of SAP XM DMP Solution at SAP Exchange Media. Throughout his career, he’s played key roles in creating groundbreaking technology to bring structure to the stores of data that digital advertising has uncovered, including the first demand-side advertising platform, the first second-party data management platform, and the first real-time cookie-less targeting.

Tom Döhler, Chief Technology Officer


CTO Tom Döhler leads Sizmek by Amazon’s Ad Serving, Applications, Data & Analytics and Integrations teams. After two years of leading the engineering team at Typeform, Tom returns to Amazon where he spent three years building the Amazon Development Center in the Netherlands and launching a new AWS service. With a combined 20 years of technology experience, he’s also worked with savvy navy, Joyn GmbH, frog design, and TomTom where he released the first versions of TomTom’s navigation software on iOS and Android. When not pioneering in the office, Tom prefers to pull anchor and sail the seas.

George Pappachen, General Counsel

George Pappachen is General Counsel for Sizmek. During his 20-plus years in practice, George has managed a full range of business and legal matters including corporate development, strategic partnerships, complex transactions, compliance, litigation, and data privacy. George has testified before the U.S. Congress, European Commission, and Federal Trade Commission on consumer data and commercial applications. In 2009, George was appointed Chief Privacy Officer of Kantar, a first for the organization and the industry.