- Full Name: Sierra Entertainment
- Also known as: Sierra On-Line
- Website: http://www.sierra.com
- State: sold out (sold to Vivendi Universal Games in 1997)
Sierra Entertainment (formerly known as Sierra On-Line) is a gaming company founded in 1980. They published the well-known King's Quest, Space Quest and Leisure Suit Larry series. Later, the company was acquired by Vivendi Universal Games but the Sierra name is still used for branding purposes.
Before the VU acquisition, Sierra acquired French company Coktel Vision along with their VMD format. Thus, VMD has been used as the FMV format for the vast majority of Sierra's multimedia adventure games and several of Coktel's titles as well.