The Ministry

The Ministry was a 20th century British defence organisation.

In 1968, Alistair was a high-up in the Ministry who went by the alias "Mother". The Eighth Doctor and "Mrs Jones" were agents of the Minstry; the Doctor wore a bowler hat during this time. After an incident involving Andy Warhol and Valerie Solanis, the Doctor and Mrs Jones were fired from the Ministry. The Ministry then gassed the Doctor and Mrs Jones and deposited them in a village. Mother approached Iris Wildthyme asking her to replace the Doctor and Mrs Jones. (PROSE: Femme Fatale)

In the 1970s, Jo Grant's friend Tara did work for the Ministry which involved "swanning about in vintage cars, doing judo and wearing a selection of not-very convincing wigs". Tara's work didn't involve any aliens. (PROSE: Verdigris)

Iris Wildthyme once worked for the Ministry, and during this time she helped Geoff Love develop the "Doctor Who theme" (PROSE: Bafflement and Devotion)

By some accounts, the Ministry's full name was "Ministry of Incursions and Ontological Wonders", or MIAOW. (PROSE: Bafflement and Devotion et al.)

Behind the scenes
The Ministry originates from the TV series The Avengers. Some of the Ministry's actions in Femme Fatale are also reminiscent of elements of. Aspects of the Doctor working for the Ministry in Femme Fatale are a nod to John Steed, and the mention of Tara in Verdigris is a nod to.