Star Trek: The Next Generation‘s sickbay set had originally been built for the aborted Star Trek: Phase II television series in the late 1970s. It was subsequently refurbished for the feature films and became the seedy bar visited by Dr McCoy in Star Trek III: The Search for Spock.
The set doubled as conference lounge during season one. In some of the earlier episodes, the outlines of where the Observation Lounge windows were hidden by carpet can be spotted.
A small medical lab was attached to the set, beyond the doors next to Dr Crusher’s office. It was crammed behind the Transporter Room set and difficult to shoot, so a separate and multipurpose laboratory was built during the third season.
The set was used pretty much unchanged in Star Trek V: The Final Frontier. It was given a more serious makeover for Star Trek VI: The Undiscovered Country.
After Star Trek: Generations, it ended up as Voyager‘s sickbay. It would later appear in Star Trek: First Contact and Star Trek: Insurrection and parts of the set appeared as the USS Prometheus‘ sickbay on the Voyager episode “Message in a Bottle.” It was torn down after the fourth series wrapped in 2001.