With the expanded surgical options provided by free tissue transfers, upper extremity reconstruction has progressed to a level of greater finesse. Recognizing the ideal tissue for restoration of function and aesthetics, thin skin dorsally and sensate glabrous skin volarly, is the first step to effective application of microsurgery in the hand. With complex deformities, all missing components must be considered and the patient's goals realistically defined. An in-depth understanding of hand function is combined with an exhaustive knowledge of free tissue donor sites and a reconstructive plan is formulated. Staged reconstruction may be necessary, depending on the complexity of the problem. Ideal donor tissues are not always available, but it is expected that advances in immunology will soon make "spare part surgery" a viable alternative.