Sima Sistani

Sima Sistani has more than 20 years of experience innovating human-centric platforms for connection. Sima has started, operated, and scaled companies from seed startups to multinational corporations. She most recently served as the CEO of WeightWatchers where she architected and led its successful transformation from a waning consumer retail company to a leading digital health platform. In 2023, CNN Business honored Sima in their annual list of 11 leaders making big bets to move global business forward. In 2024, she was recognized by CNBC as a “Changemaker” for her leadership in transforming business and diet culture. Sima is also an avid Yogi and Professor at Duke University.

Prior to her joining WW in March 2022, Sima was the Co-Founder and CEO of Houseparty, a communication app. Houseparty, which grew to over 100M users under her leadership, challenged the incumbent social media giants with its innovative approach to synchronous chat and a business model that respected data privacy and prioritized trust & safety. Epic Games acquired the company in 2019. At Epic, Sima joined the senior leadership team, where she was responsible for social products across Epic Games, including Fortnite, one of the world’s most popular game titles ever released, with over 350 million registered users.

Prior to founding Houseparty, Sima led Mobile Growth at Yahoo. During her tenure, the company’s stock doubled in value and saw the mobile team scale from less than 30 to over 300 people. After Yahoo acquired Tumblr, Sima played a key role in bridging the two entities as Head of Media for the emerging microblogging and social media giant. Tumblr became the fastest-growing social network in active users in just 6 months.

Sima began her career at Goldman Sachs in International Equities and eventually moved from the trading floor to Hollywood, Creative Artists Agency. She holds a BA from Duke University and an MBA from Northwestern University, Kellogg School of Management. She sits on the board of Best Buy and is a 2023 Aspen Institute Henry Crown Fellow. Sima is a first-generation American and lives in North Carolina with her husband and two children.