Common tumors of the hand and upper extremity are, by definition, benign conditions. There is a predictable pattern of occurrence and presentation for many of these lesions. The practitioner should always bear in mind, however, that any tumor that appears anywhere in the body can appear in the hand and upper extremity. Moreover, several of the benign conditions can, in certain clinical settings, have a predilection for transformation or association with more aggressive conditions. We would emphasize that the approach to any tumor be carefully considered and include an appropriate differential diagnosis. Any suspicious lesion should be examined thoroughly, including first-order screening tests, history, physical examination, radiographic imaging, and laboratory evaluations followed by more detailed diagnostic imaging prior to surgery. Surgery should be approached as a biopsy, with the possibility of frozen section analysis, and the possibility of a two-staged operation for tumor removal with appropriate margins if necessary.