Basal cell and squamous cell skin cancers, collectively known as non-melanoma skin cancers (NMSCS), are the most common skin cancers. More than 1 million cases of NMSC are estimated to be diagnosed each year in the United States and their incidence is rising rapidly. Although rarely metastatic, basal cell and squamous cell cancers can produce substantial local destruction and disfigurement and may involve extensive areas of soft tissue, cartilage, and bone. Updates in the 2007 guidelines include changes to the principles of treatment for both basal cell and squamous cell skin cancers and changes in the consideration of radiotherapy. © Journal of the National Comprehensive Cancer Network.