Colorectal cancer (CRC) is the 2nd most commonly diagnosed cancer and the 3rd most common cause of cancer death among both men and women in Australia. It is a complex disease that arises from differential impacts of environmental factors, including diet and lifestyle choices on different genetic backgrounds. Obesity – particularly central adiposity – and type 2 diabetes are significant risk factors for CRC. While the association of obesity with CRC is known, the mechanisms by which obesity contributes to CRC are unknown. CRC is projected to be the most common cancer in Australia in 2025, largely as the result of diet and lifestyle factors. Understanding the link between obesity and colorectal cancer is important for potential intervention and screening strategies. To investigate this association we have established tissue, microbial and blood collections from lean and obese individuals with CRC undergoing colorectal cancer resection. This collection is unique due to the breadth of clinical specimens, the rapid stabilization of tissues in RNAlater (Ambion) and the comprehensive background clinical and demographic information collected from study participants. Collected tissues include colon tumour; normal colon tissue proximal and distal to the tumour and adjacent visceral adipose tissue and a digesta sample. Participants complete questionnaires on perceived stress, physical activity, food frequency and medical history. Twelve individuals (6 lean and 6 obese) have been selected for complementary next-generation sequencing of RNA from normal colon, colon tumor, adipose and microbial samples to facilitate a comprehensive approach to dissecting the link between obesity and colon cancer.