Guidelines for the surgical treatment of cutaneous primary malignant melanoma are well established; however, the approach to the treatment of the regional lymph nodes remains more controversial. In many centres, sentinel lymph node biopsy has been adopted as routine in the treatment of malignant melanoma for prognostic purposes, as it is not of proven therapeutic benefit. The Multicentre Selective Lymphadenectomy Trial II aims to determine the comparative benefits of subsequent completion lymphadenectomy versus observation in those found to have a positive sentinel node biopsy. Until results are available, the risks of the procedure must be weighed against the value of prognostic information gained from performing a sentinel node biopsy. In this retrospective analysis of sentinel lymph node biopsies at our institution, we show that in general, short-term morbidity associated with this procedure is low, but that morbidity is higher in a subgroup of people with higher weight or body mass index, and in those whose biopsy is located in the groin.