Eleni Nicholas is the Chief Client Officer at MediaMath. She is responsible for driving success for clients and bringing assurance that their advertising dollars will be effectively and strategically utilized. Before joining the MediaMath team, Eleni spent 28 years at Nielsen where she served in a variety of commercial, client-facing, and organizational transformation roles. Her experience within Nielsen included serving as the Global Leader of the Top 35 fast-moving consumer goods clients of Nielsen, launching new vertical practice areas of Nielsen Europe, and serving as Global Client Business Partner for Unilever. She is a champion and sponsor for diversity and inclusion and has led numerous initiatives promoting diversity, including launching Women in Nielsen for Europe and participating as an active mentor for the Women’s Leadership Program.