This report presents the findings of an intervention study investigating the reasons for referral to oncology social workers and the types of interventions undertaken by them. The study was an academic and practitioner collaboration between the University of Sydney and practitioners from six cancer care settings in metropolitan, regional and rural centres in New South Wales, Victoria and Queensland. Clinical data mining methodology was used, with a cross analysis of key variables mapped to existing social work classification systems. The findings indicated that high-level relationship-based skills were required to deliver social work services. Key domains of social work practice were linked to health inequalities. Areas for further research were identified including greater engagement with Aboriginal and Torres Strait Islander patients, the need for improved health literacy about the role of social work in their cancer treatment and the need for increased access to social workers and cancer services in rural and regional centres.