Sonic & Knuckles Collection is a Sonic the Hedgehog compilation game for Microsoft Windows-based PCs, released in 1997.

This collection includes:

Sonic the Hedgehog 3
Sonic & Knuckles
Sonic 3 & Knuckles
Blue Sphere

The European and North American versions of the collection also includes Sonic the Screensaver which the player can customize Windows with Sonic themes, wallpapers, icons, and music from Sonic 1, 2, 3 and Sonic & Knuckles, and the Japanese & European soundtrack of Sonic the Hedgehog CD in 11 kHz WAV format. However, in Japan, Sonic & Knuckles Collection and Sonic the Screensaver were released separately, on the same day. Some tracks in Sonic the Hedgehog 3 were replaced due to sound card limitations.

This game is virtually impossible to play in windowed mode on any system with a CPU faster than 350 MHz, because the game does not have speed-limiting routines enabled in this mode. The timings used by the game are based on the monitor's refresh rate. Switching the game to fullscreen mode lets the game play properly, no matter what the system speed is. In windowed mode, the game can be played at the correct speed whenever the screen refresh rate is at 60Hz. Sega has also provided a patch to fix this problem without reducing the refresh rate.