Fink is set to headline Bushstock 2011 when it debuts across four venues around Shepherds Bush, London on Saturday 7 May.
Tom Williams And The Boat, Sarah Blasko and country soul group Treetop Flyers have also been added.
Cloud Control and The Staves have been confirmed too with many more to be confirmed in the coming weeks.
Bushstock 2011 will feature 30 amazing emerging acts for the UK and abroad.
First acts are to be unveiled in the coming weeks.
Communion started promoting club nights in 2006 with monthly shows in London. Four years on and with a reputation for championing the most exciting new music around, the Communion family has grown to include nine monthly club nights on three continents and a record label which has released numerous EPs and albums.
Early bird tickets have all sold out but tickets are now on general sale priced at £27.50.