Mark Evan Cerny (/ˈsɜːrni/ SUR-nee; born August 24, 1964) is an American video game designer, programmer, producer and media proprietor.

Raised in the San Francisco Bay Area, Cerny attended UC Berkeley before dropping out to pursue a career in video games. In his early years, he spent time at Atari, Sega, Crystal Dynamics and Universal Interactive Studios before becoming an independent consultant under his own company Cerny Games in 1998. While at Sega, he established Sega Technical Institute, working on games including Sonic the Hedgehog 2 (1992).

Cerny has since frequently collaborated with Sony Interactive Entertainment as a consultant, including being the lead designer for hardware of several PlayStation consoles, being called the architect of the PlayStation Vita, PS4 and PS5. He has also consulted with Naughty Dog and Insomniac Games since their creation in the 1990s, as well as other Sony first-party studios like Sucker Punch Productions. He has also developed several games, notably the arcade game Marble Madness and the Knack series, and has been credited on many more for his consulting work.

In 2004, he was the recipient of the Lifetime Achievement Award from the International Game Developers Association, and was inducted into the Academy of Interactive Arts & Sciences Hall of Fame in 2010.

Mark Evan Cerny was born in 1964 or 1965. He grew up in San Francisco, and was a fan of computer programming and arcade games as a youth. He had attended University of California, Berkeley, but when he was 17 in 1982, he was invited to join Atari, and dropped out of school for the opportunity. He started working in Atari's arcade division on January 18, 1982. In those earlier days of professional game development, teams were small and each member was responsible for a wider range of roles than today. He first worked with Ed Logg on Millipede and Owen Rubin on Major Havoc. "Working at Atari early in my career was an experience I'll never forget. I got to work alongside game design legends like Ed Logg, Dave Theurer, Owen Rubin, among many others, during a time when creativity, passion and competition was at a high. Ideas that were 100% original was not only expected, but demanded. As a young 18-year-old, I couldn't ask for a better introduction for my career," said Cerny.

Cerny's first major success was the arcade game Marble Madness in which he, at age 18, acted as designer and co-programmer. During this period around 1985, he gained an interest in video game hardware, which Cerny considered far simpler than his later work with the PlayStation. By the end of the 1980s, he joined Sega, initially working at Sega's headquarters in Japan and then returning to the United States by 1991 to help establish the Sega Technical Institute. There, he worked on various Master System and Genesis releases, most notably Sonic the Hedgehog 2.

Cerny left Sega in 1992 to join the newly formed Crystal Dynamics. He initially worked on 3DO games including Crash 'n Burn (1993) and Total Eclipse (1994). Cerny was instrumental in helping Crystal Dynamics become the first American developer to secure a PlayStation development kit from Sony Computer Entertainment, having gone to Japan to negotiate the deal with Shuhei Yoshida, at that point a young executive within Sony. While the development kit had been delivered to Crystal Dynamics by 1994, Cerny had left the studio to lead Universal Pictures' newly formed multimedia division.

From 1994 to 1998, Cerny was involved with Universal Interactive Studios, a newly formed division of Universal for video games that Cerny described as a "boutique publisher". Cerny was initially a vice president of product development and later became its president. Cerny had been given a good amount of freedom with the division, stating "The best part about this was that Universal didn't really know the business and as a result I had a great big bag of money to spend and no supervision". Under Cerny, Universal Interactive Studios hired in two small and new development studios to develop for the PlayStation, aided by his past connections within Sony: the three-person Naughty Dog and two-person Insomniac Games. In the case of Naughty Dog, they were brought in to build Way of the Warrior and had signed on for three additional titles. Cerny helped with their next title, Crash Bandicoot, which Sony picked up to publish in 1996. Insomniac similarly had completed their first title Disruptor and Cerny helped them prepare the next game, Spyro the Dragon, which also was picked up and published by Sony in 1998. When Naughty Dog and Insomniac's contracts with Universal expired, both studios signed up with Sony to continue to develop games for the PlayStation. Cerny kept in close contact with both teams afterwards. In 1998, Universal as a whole had financial issues that set a hiring freeze on the Interactive Studios group. Cerny opted to leave Universal to become consultant under his own company, Cerny Games, that would allow him to keep working with Naughty Dog, Insomniac and Sony.