In 1981, he founded the Dutch Film Days, a festival created to provide Dutch directors with an opportunity to screen their films and to foster a more informal and collaborative environment. Stelling served as chairman and director of the festival until 1991, after which the event was renamed the Netherlands Film Festival.
Stelling is the founder and owner of three arthouse cinemas in Utrecht: Springhaver (opened in 1978), the Louis Hartlooper Complex (opened in 2004) and Slachtstraat filmtheater (opened in 2022)