The use of tissue expanders having external reservoirs is presented. Twenty-four patients had 36 tissue expanders placed in the scalp, face, neck, upper limbs, chest, and lower limbs. All patients, apart from one, were taken to completion. This patient had erosion of the skin over expander and was only partially completed after removal of the expander. Apart from one instance of deflation at the end of the expansion where the skin could still be used, there were no other complications, in particular, no infections. The advantages of this technique are reduced operating time, ease of injection into the reservoir, lack of pain for the patient, early detection of reservoir or filling tube junction leakage, and lack of complications associated with the reservoir. This procedure is not recommended on at least theoretical grounds for breast expansion, where a permanent implant is to be inserted.