The effects of IR will be investigated in comparison to Imaginal Exposure (IE) and Supportive Counselling (SC). IR targets imagery-based mental representations embedded within patients autobiographical memories. In IR, patients progress through 3 distinct phases: (1) Participants "relive" a past negative event in their imagination, (2) are guided to actively change the original memory in their imagination to create more satisfying outcomes, and (3) relive the memory again while incorporating the new information. IE involves repeatedly "reliving" the memory from a first-person perspective and actively considering alternative meanings of the memory, but differs from IR in that the original memory itself is never explicitly modified in any way. SC provides patients with empathic support and controls for non-specific clinical factors such as therapeutic attention and alliance. The research will examine whether IR outperforms these conditions and leads to sustained changes in SAD symptoms, quality of life, and social behaviour. The use of IE as a control condition will help to determine whether the therapeutic effects of IR depend on altering the content of the targeted autobiographical memory rather than just its meaning.