The logo of the Symbiosis Commission.
The Symbiosis Commission is the Trill organization responsible for the nearly all aspects of the joining of a Trill host and symbiont.
The Guardians work for the Commission and care for the symbionts before they are joined in the Caves of Mak'ala. (DS9: "Equilibrium")
The Commission oversees the selection process for potential hosts and symbionts. Host initiates must pass all required tests and have their application approved by the Commission in order to become joined. Even then the Commission remains an authority in the joined Trill's life. They continue to care for the symbionts and give counselling for hosts; this includes requiring that joined Trill perform the Zhian'tara as a means of dealing with the memories of previous hosts. Joined Trill may serve the Commission by acting as field docent to prospective hosts. (DS9: "Facets, Playing God")
The Commission also controls information regarding the symbionts. After an unsuccessful joining between the Dax symbiont and Joran Belar, the Commission made it appear that only one Trill in a thousand were capable of being joined. In fact, nearly half of the population were capable. (DS9: "Equilibrium")
- The Commission may also be responsible for concealing the joined nature of the Trill, which was not a public fact until 2367 when a crisis involving ambassador Odan revealed it.
Curzon Dax was a member of the Symbiosis Comission. Audrid Dax served as Head of the Commission. (DS9: "Facets")