From 5/88 to 8/93 148 patients were operated on for obstructive azoospermia using a microsurgical technique. In 68 patients we performed a vasectomy reversal by vasovasostomy (VT), 42 patients underwent a tubulovasostomy (TT), and 8 patients had a VT with contralateral TT. Two patients had implantation of an alloplastic spermatocele, 9 patients had microsurgical epididymal sperm aspiration (MESA), and 19 patients microsurgical exploration. Patency was achieved in 89% of patients after VT and in 32% after TT. A pregnancy occurred in 34% after VT and in 13% after TT. No pregnancy was achieved after MESA or alloplastic spermatocele. A microsurgical procedure is necessary for the treatment of congenital or acquired obstructive azoospermia.