Big Finish releases a free CD with two audio dramas, one of them a stand-alone Bernice Summerfield adventure and the other a prelude to the upcoming UNIT audio series featuring Nicholas Courtney as the Brigadier, attached to the cover of Doctor Who Magazine issue #351. Both audio stories are later made available on the Big Finish website. 
Big Finish Productions releases the first U.N.I.T. audio drama, a Doctor Who audio spinoff featuring Nicholas Courtney as Brigadier Lethbridge-Stewart leading a new cast of characters.
Big Finish Productions releases the second U.N.I.T. audio drama, a Doctor Who audio spinoff.
Big Finish Productions releases the third U.N.I.T. audio drama, a Doctor Who audio spinoff.
Big Finish Productions releases the fourth U.N.I.T. audio drama, a Doctor Who audio spinoff. Nicholas Courtney and David Tennant guest star in what is intended to be a “season finale”, though it will be several years before Big Finish revisits U.N.I.T. as its own audio spinoff.
Big Finish Productions releases U.N.I.T.: Dominion, a standalone Doctor Who audio drama starring Sylvester McCoy and Tracey Childs. This story is nrelated to Big Finish’s earlier U.N.I.T. audio series.
Big Finish Productions releases the U.N.I.T.: Exctinction audio drama box set featuring the episode Vanguard. This is an audio spinoff series based on the modern series iteration of U.N.I.T., starring Jemma Redgrave and Ingrid Oliver.
Big Finish Productions releases the U.N.I.T.: Exctinction audio drama box set featuring the episode Earthfall. This is an audio spinoff series based on the modern series iteration of U.N.I.T., starring Jemma Redgrave and Ingrid Oliver.