This report summarises key operational statistics and outcomes of ASIC’s market and participant supervisory functions in relation to ASX, ASX 24 and other Australian market licensees for the period 1 July 2011 to 31 December 2011. Of particular note is that four people were found guilty of insider trading and all of them agreed to plead guilty promptly after discussions with ASIC. Further, during this time, there were 20,029 trade surveillance alerts. ASIC conducted enquiries into 131 market matters. A total of 23 matters were referred to ASIC’s Deterrence team for formal investigation. ASIC also engaged with market participants in relation to market matters on 21 occasions, including raising concerns about potentially disruptive execution strategies, and algorithmic trading issues.