Lipomas are benign skin tumors composed of mature fat cells and are the most common subcutaneous tumors. Although many of these can be removed in the surgical clinic or minor operating room, some require more advanced preoperative planning and more complicated resection. The diagnosis, pathology, and treatment of benign tumors, and other commonly associated tumors that may require a more substantial workup and operative intervention, are discussed. Muscle and nerve biopsies are used for the diagnosis of a variety of medical problems. Although there are other genetic and biochemical markers now available that can diagnose diseases previously proven by biopsy, these surgical techniques still have appropriate uses. Although the procedures are straightforward, there are important technical issues to assist in getting the best specimen to avoid confounding disease diagnosis.