Obesity is a major problem not only in humans but also in pet animals. It is a risk factor for diabetes mellitus. Our group has primarily focused on obesity and diabetes mellitus in cats. Cats develop similar defects in insulin secretion and peripheral insulin action as obese people and people with type 2 diabetes mellitus. Cats also develop islet amyloid with diabetes. Apart from cats, this is only seen in diabetic people and the macaque monkey. Cats are therefore excellent models for the disease in people. We are especially interested in factors that are involved in the progression from obesity to diabetes. In addition, we are examining nutritional and pharmacological agents that might prevent the defects in insulin secretion and/or action seen in obese humans and pets. We are also developing feline specific assays which could be used to identify cats at risk.