The following broadly outlines the Starship/Starbase diplomatic grading system currently used by Starfleet. Note that classes are not required to be an exact match to these facilities in order to receive a grade; rather they must be broadly in line with the level of capability implied by the assigned grade.
| Grade | Facilities | Classes |
| 75 x Ambassadorial quarters at 250 square meters each. 2,250 x Staff quarters at 30 - 80 square meters each 4 x 2,500 square meter conference hall complexes for 600 guests each 75 x 150 square meter 40 seat briefing rooms 75 x Independent communications facilities 30% of all facilities, including interconnecting corridors, capable of supporting H, K, or L environments Facilities for up to 400 members of the press | Galaxy, Nebula Starbases often contain | |
| 30 x Ambassadorial quarters at 210 square meters each. 900 x Staff quarters at 25 - 60 square meters each 2 x 1,500 square meter conference hall complexes for 500 guests each 30 x 150 square meter 40 seat briefing rooms 30 x Independent communications facilities 25% of all facilities, including interconnecting corridors, capable of supporting H, K, or L environments Facilities for up to 150 members of the press | Ambassador | |
| 20 x Ambassadorial quarters at 100 square meters each. 400 x Staff quarters at 15 - 25 square meters each 1 x 1,000 square meter conference hall complexes for 450 guests 20 x 90 square meter 25 seat briefing rooms 20 x Independent communications facilities 15% of all facilities, including interconnecting corridors, capable of supporting H, K, or L environments Facilities for up to 50 members of the press | Excelsior, Sovereign | |
| 5 x Ambassadorial quarters at 50 square meters each. 50 x Staff quarters at 15 square meters each 1 x 120 square meter conference hall complexes for 60 guests 5 x 50 square meter 15 seat briefing rooms One independent communications facility 15% of all facilities, including interconnecting corridors, capable of supporting H or K environments | Norway, Miranda, Lakota-type Excelsior | |
| Diplomats housed in crew quarters if required 1 x 80 square meter conference room for 40 guests 2 x 40 square meter 10 seat briefing rooms Communications via standard ships systems 15% of all facilities, including interconnecting corridors, capable of supporting H or K environments | Akira, Steamrunner, Intrepid, New Orleans | |
| Diplomatic courier function only - diplomats housed in crew quarters for short duration interstellar missions. | Defiant, Saber, some Oberth subtypes, Prometheus, some Runabouts | |
| Diplomatic courier function only - diplomats housed in crew quarters for short duration interplanetary missions. | Most Oberth vessels, Runabouts and Shuttlecraft, Colony transports, Cargo and support vessels |