Abstract : Diabetic foot is a common complication of diabetes mellitus. Its pathophysiology is most often complex with the interconnection of three different components : diabetic neuropathy, arterial disease and infection. The diagnostic approach should specify the respective role of each component, firstly thanks to a thorough medical interview and a careful clinical examination. Afterwards, well selected complementary exams will confirm the hypotheses generated by the initial clinical approach. Consequently, a specific care strategy will be implemented, ideally with the help of a multidisciplinary team. This educational clinical case is devoted to the sequential diagnostic approach of a patient with a foot ulcer in the context of a diabetic foot.