He joins Sunderland from Australian outfit Sydney FC.
Sydney FC chairman, Walter Bugno, had this to say:
"Dwight Yorke has made an unbelievable contribution to Sydney FC and Australian football and we wish him nothing but luck in his new endeavours with Sunderland," Bugno said.
"Sydney FC has always maintained that marquee players have an important role to play in the early stages of the Hyundai A-League. Before the A-League started we believed in the principal of a marquee player and now we have seen the advantages, on and off the field, we will set out to find another player who can contribute as much to the game as Dwight has since he arrived last year.
"Our coaching staff will start drawing up a list of targets straight away and I am in Europe for the next two weeks so I am available to meet with any prospective marquee players."