A first officer (aka executive officer, XO, and number one) is the second-highest ranking officer aboard a starship or space station after the commanding officer. He or she takes command if the commanding officer is unable to. If the first officer is also unable to take command, the second officer is in charge, followed by the third officer, and so on. On ships assigned to the Starfleet Corps of Engineers, such as the USS da Vinci, the first officer is concurrently the leader of the team.

First officers by nameEdit

• A captain who previously served as commander and first officer of the USS Dauntless under Captain Robert Wright.
• Commander Saffi Larsen of the USS Dauntless and the USS Sovereign
• Commander Samir al-Halak of the USS Enterprise-C (2336-?)
• Commander Sam Bowers of the USS Aventine (2381-current)
• Commander Burgoyne 172 of the USS Excalibur-A (2376-current)
• Lieutenant Commander Aaron Cavit of the USS Voyager (2371)
• Lieutenant Commander Chakotay of the USS Voyager (2371-2378)
• Commander Domenica Corsi of the USS da Vinci (2380-current)
• Captain Willard Decker of the USS Enterprise (2273)
• Commander Quint Freedman of the USS Incursion (2377)
• Commander Sonya Gomez of the USS da Vinci (2375-2380)
• Major Kira Nerys of Deep Space 9 (2369-2375)
• Lieutenant Commander George Samuel Kirk, Sr. of the USS Enterprise (2243)
• Commander Martin Madden of the USS Enterprise-E (2379)
• Number One of the USS Enterprise (2251-2264)
• Lieutenant Commander Thomas Paris of the USS Voyager (2378-current)
• Commander Dakona Raal of the USS Orion
• Commander William T. Riker of the USS Enterprise-D (2364-2371) and the USS Enterprise-E 2372-2379)
• Commander Salek of the USS da Vinci (?-2375)
• Commander Elizabeth Shelby of the USS Chekov (2367) and the USS Excalibur (2368-2376)
• Commander Lorna Simon of the USS Enterprise (2245-2251)
• Commander Shundresh of the USS Enterprise (2245-2251)
• Commander Spock of the USS Enterprise (2264-2281)
• Captain Spock of the USS Enterprise-A (2286-2293)
• Commander Demora Sulu of the USS Enterprise-B (2301-2311)
• Commander Christine Vale of the USS Titan
• Commander Worf of the USS Enterprise-E (2380-current)
• Commander Gilaad Ben Zoma of the USS Stargazer

First officers by postEdit

• USS Aventine: Commander Sam Bowers (2381-current)
• USS Chekov: Commander Elizabeth Shelby
• USS da Vinci
  • Commander Salek (?-2375)
  • Commander Sonya Gomez (2375-2380)
  • Commander Domenica Corsi (2380-current)
• Deep Space 9: Major Kira Nerys (2369-2375)
• USS Enterprise
  • Lieutenant Commander George Samuel Kirk, Sr. (2243, MIA)
  • Commander Shundresh (2245)
  • Commander Lorna Simon (2245-2251)
  • Number One (2251-2264)
  • Commander Spock (2264-2270; 2273-2281)
  • Captain Willard Decker (2273)
• USS Enterprise-A: Captain Spock (2286-2293)
• USS Enterprise-B: Commander Demora Sulu (2301-2311)
• USS Enterprise-C: Commander Samir al-Halak (2336-?)
• USS Enterprise-D: Commander William Riker (2364-2371)
• USS Enterprise-E
  • Commander William Riker 2372-2379)
  • Commander Martin Madden (2379-2380)
  • Commander Worf (2380-current)
• USS Excalibur: Commander Elizabeth Shelby (2368-2376)
• USS Excalibur-A: Commander Burgoyne 172 (2376-current)
• USS Incursion: Commander Quint Freedman (2377)
• USS Orion: Dakona Raal (?-2376)
• USS Stargazer: Commander Gilaad Ben Zoma (2333-2355)
• USS Titan: Commander Christine Vale (2379-current)
• USS Voyager
  • Lieutenant Commander Aaron Cavit (2371)
  • Lieutenant Commander Chakotay (2371-2378)
  • Lieutenant Commander Thomas Paris (2378-current)

First officers by yearEdit

• 2243 - Lieutenant Commander George Samuel Kirk, Sr. of the USS Enterprise
• 2245 - Commander Shundresh of the USS Enterprise
  • Commander Lorna Simon of the USS Enterprise
• 2251 - Number One of the USS Enterprise
• 2264 - Lieutenant Commander Spock of the USS Enterprise
• 2273 - Captain Willard Decker of the USS Enterprise
• 2286 - Captain Spock of the USS Enterprise-A
• 2301 - Commander Demora Sulu of the USS Enterprise-B
• 2333 - Commander Gilaad Ben Zoma of the USS Stargazer
• 2336 - Commander Samir al-Halak of the USS Enterprise-C
• 2364 - Commander William T. Riker of the USS Enterprise-D
• 2367 - Commander Elizabeth Shelby of the USS Chekov
• 2368 - Commander Elizabeth Shelby of the USS Excalibur
• 2369 - Major Kira Nerys of Deep Space 9
• 2371 - Lieutenant Commander Aaron Cavit of the USS Voyager
  • Lieutenant Commander Chakotay of the USS Voyager
• 2372 - Commander William T. Riker of the USS Enterprise-E
• 2375 - Commander Salek of the USS da Vinci
  • Commander Sonya Gomez of the USS da Vinci
• 2376 - Commander Burgoyne 172 of the USS Excalibur-A
  • Commander Dakona Raal of the USS Orion
• 2377 - Commander Quint Freedman of the USS Incursion
• 2378 - Lieutenant Commander Thomas Paris of the USS Voyager
• 2379 - Commander Christine Vale of the USS Titan
  • Commander Martin Madden of the USS Enterprise-E
• 2380 - Commander Worf of the USS Enterprise-E
  • Commander Domenica Corsi of the USS da Vinci
• 2381 - Commander Sam Bowers of the USS Aventine