Observation lounge
The observation lounge or conference lounge was a special designation referring to the briefing room on Excelsior-, Galaxy-, , and  starships as well as on the Reman warbird Scimitar. It included an expansive view of space on one side of the room. (; ; )

Starfleet design 
Aboard Starfleet vessels, the observation lounge was used as a meeting place for the ship's senior staff as well as special events and gatherings. Some went to the observation lounge simply for the view. Admiral Jameson usually found himself in the ship's observation lounge, looking out at the stars, just prior to a mission. (; )

On both the Galaxy- and Sovereign-classes, the room was elongated, spanned the entire area aft of the bridge on Deck 1 and featured a large conference table. There was also a series of seven viewports, composed of transparent aluminum. () These viewports spanned from close to the floor to up along the angled ceiling, which faced the rear of the ship. ()

Excelsior-class 

The observation lounge on the Excelsior-class was located on the same deck as the main bridge. 

In 2293, the location of this lounge was labeled on a MSD of the . ()

Galaxy-class 

The observation lounge on the Galaxy-class was connected to the bridge through a short, ramped corridor, which originated at the upper starboard alcove of the bridge and led to a door on the starboard side of the conference lounge. Another door, on the port side of the room, led to another corridor, () at the end of which was a turbolift. The shape of the conference table matched the curvature of the exterior hull, and had seating and data pads for ten individuals. The captain usually sat at the head of the table, at either side. In 2365, two display screens were added and located at either side of the room, behind the table and adjacent to the doors. The observation lounge was decorated by plants, and had two replicator terminals. () The room was also fitted with audio and visual recording devices behind a panel. ()

USS Enterprise-D
For a number of years, the wall opposite the windows on the  featured an -style display of scale sculptures of six of the Earth vessels previously commissioned as the USS Enterprise as of 2364. ()

In 2366 of an alternate timeline, the battleship Enterprise-D had an observation lounge which omitted the display of Enterprise models and seemed to have only one door. However, the conference table was still a feature of the room, as was a row of windows built into one of the walls. The conference table was at waist height so that occupants stood at the table. One addition was a large tactical graphic of the Enterprise-D, illustrated in blue and yellow on a transparent, vertical stand. ()

The display of Enterprises was removed, for unspecified reasons, in 2368. Also at this time, ribbed light vents were added below the windows. () The redress of the set for Star Trek VI: The Undiscovered Country gave the production team an excuse to redesign the set for Season 5. The gold ships on the wall were rescued from a dumpster by Ronald D. Moore after he had been tipped off by Michael Okuda that they were being discarded.[3]

In 2369, the display screens were permanently illuminated, with the port display showing information about the Enterprise systems and the starboard display giving status reports of various Starfleet vessels. ()

The conference lounge served a multitude of purposes; in addition to being a meeting place, it could also host informal parties () and held events for "Captain Picard Day". ()

In late 2367, the observation lounge was decompressed after the transparent aluminum of a window was temporarily phased out of normal space by pockets of subspace instability in a dark matter nebula. ()

In 2370, effects due to the D'Arsay archive transformed the observation lounge into a swamp. ()

Sovereign-class 

The layout of the Sovereign-class observation lounge was similar to that of the Galaxy-class; the conference table was curved in a similar manner, and there was also the same number of seats. However, the room connected directly to the bridge via two doors on either side of the master systems display. Steps inside the lounge led down to the table level. The room also lacked viewscreens during the early 2370s.

USS Enterprise-E 
In 2373, the  conference lounge also had a "past Enterprises" display, though it took the form of a large glass case enclosing seven full models on stands (the Enterprise-D being the most recent). The display was damaged when Captain Jean-Luc Picard smashed the case with a phaser rifle in a fit of hysteria following an attack from his one-time abductors, the Borg. ()

By 2379, the case was split to either side of a new, large computer terminal and the doors were relocated. ()

de:Aussichtslounge
fr:Salon d'observation
pl:Pokój odpraw
Spacecraft sections