Searching for restitution in Australia / Keith Mason -- The structure and challenges of unjust enrichment / Mitchell McInnes -- Change of position: the nature of the defence and its relationship to other restitutionary defences / Peter Birks -- Change of position: commentary / Michael Bryan -- Benefits-for services rendered / David Byrne -- Benefits-for services rendered: commentary / Michael Garner -- Restitutionary recovery of taxes after the Royal Insurance case / J. D. Merralls -- Restitutionary recovery of taxes after the Royal Insurance case: commentary / John Glover -- Restitution and contract risk / J. W. Carter -- Restitution and contract risk: commentary / Kwai-Lian Liew