Abstract A new operative technique using synthetic, absorbable mesh for grafting a urethral defect was applied in 7 mongrel male dogs. The ventral half of the urethral circumference with its surrounding corpus spongiosum was excised for a length of 3 to 4 cm. A Dexon mesh of the same dimensions, woven in our laboratory from polyglycolie acid fibers, was sutured to the defective area. A perineal urethrotomy was established, and no splints were left behind. Dogs were studied between two and six months. Retrograde urethrography showed that the operative area healed without strictures or irregularities. Intravenous urography showed no back pressure effects, and cultured urine was always sterile. Histologic examination two months after surgery showed that the urothelium was completely healed, without inflammatory changes or disruption. Suburothelial tissues were replaced by dense collagenous connective tissue. The excised corpus spongiosum did not regenerate. After six months, the area of dense collagen described was diminished in size so that the operative area could be hardly identified except by the absence of corpus spongiosum.