The armed faction that contested Turkana IV with the Coalition and took the crew of the freighter Arcos hostage, prompting an Enterprise rescue mission in 2367.
The Alliance is one of the two cadres that rule what is left of the Turkana IV colony, a world that had cut its ties with the Federation and warned that trespassers would be killed. Like its rival the Coalition, it grew out of the gangs that filled the gap when the colonial government fell apart.
In the Next Generation episode Legacy, two crewmen of the Federation freighter Arcos land in an escape pod and are seized by the Alliance, which hopes to bargain with them. Captain Picard is reluctant to deal with either faction.
An away team guided by Ishara Yar frees the hostages from the Alliance's headquarters, while Ishara tries to disable the fusion reactor that powers the Alliance's defences so that the Coalition can overrun it. Her plan is foiled, leaving the balance between the cadres unchanged.