Early attempts at surgical sperm retrieval focused on creating artificial spermatoceles in men with vas aplasia or uncorrectable obstructive azoospermia. The collected sperm was used for intrauterine insemination, and success was rare. The major impetus to sperm retrieval came soon after the development of intracytoplasmic sperm injection, which enabled high fertilization rates and live-birth rates using sperm from the testis or epididymis. Initial cases involved men with obstructive azoospermia and sperm were retrieved microsurgically from the epididymis. Subsequently, testicular sperm, obtained by conventional biopsy, were used when sperm could not be aspirated from the epididymis. Retrieval was simplified with the development of percutaneous techniques for extracting epididymal or testicular sperm. Techniques became more complex and varied when it was realized that men with nonobstructive azoospermia may also have sperm in their testes, but these sperm-containing tubules could be very localized. Hence, a variety of percutaneous and open methods were developed that could sample the testes extensively. Initially the sampling was blind, through multidirectional aspiration or multiple random biopsies. However, these blind techniques could still miss localized areas of sperm production. Also, multiple biopsies were shown to cause testicular damage. Hence, microdissection testicular sperm extraction (mTESE) was developed, which involved visual inspection of the entire testicular parenchyma under high magnification. mTESE gives the highest sperm retrieval rates, especially when the testes are small or atrophic.