Circumcision surgical procedure in males involves either a "cut and stitch" surgical procedure or use of a circumcision instrument or device. In the newborn period (less than 2 months of age), almost all circumcisions are done by generalist practitioners using one of three surgical instruments. In the US, the Gomco clamp is the most utilized instrument, followed by the Mogen clamp and the Plastibell. They are also used worldwide.

Complications may include bleeding, infection, reduction in sensation of the glans penis, and too little or too much tissue removal. Deaths are rare with estimates between 1 in 10,000 and 1 in 100,000 in hospital settings. After the newborn period, circumcision has a higher risk of complications, especially bleeding and anesthetic complications.

In the 21st century, most circumcisions in boys and men are performed using one of three open surgical methods. The forceps-guided method, the dorsal slit method, and the sleeve resection method are well described by the World Health Organization in their Manual for Male Circumcision under Local Anaesthesia. The Gomco clamp and Mogen clamp are sometimes used after the newborn period, in conjunction with either surgical sutures or cyanoacrylate tissue adhesive to prevent post-operative bleeding.

Circumcision surgical instruments should be distinguished from circumcision devices. Circumcision instruments are used at the time of surgery, and the circumcision is complete at the end of the procedure. The Gomco clamp, the Mogen clamp, and Unicirc are surgical instruments. Circumcision devices remain on the penis for 4 to 7 days and either spontaneously detach or are removed surgically at a subsequent visit. Plastibell, Shang Ring, and other plastic rings are all circumcision devices, also known as "in situ" devices. Circumcision via instrument results in healing by primary intention and healing via devices is by secondary intention, so healing is delayed. All circumcision procedures should involve adequate injectable or topical anesthesia.

The Gomco clamp is a surgical instrument used to perform circumcision in all age groups, but is mainly used in newborn circumcision. It is the leading instrument for newborn circumcision in the US. The World Health Organization described it as having "an impeccable safety record" in 2010.

After retracting the foreskin, the Gomco bell is placed over the glans at the level of the corona and the foreskin is replaced into the anatomic (natural) position. The yoke is then placed over the bell, trapping the foreskin between the bell and the yoke. The clamp is tightened, crushing the foreskin between the bell and the base plate, and left in place for five minutes. The crushed blood vessels provide hemostasis. The flared bottom of the bell fits tightly against the hole of the base plate, so the foreskin may be cut away with a scalpel from above the base plate, the intent being a lower risk of injuring the glans.

Circumcision is rapid and completed in a single session. The total procedure takes less than ten minutes, five minutes of which is spent in waiting for the crushing action to take place. In newborns (<2 months of age), no sutures are needed and bleeding is uncommon. After the newborn period, either sutures or cyanoacrylate tissue adhesive can be used to seal the fused mucosal-skin edge to prevent post-operative bleeding. Because the glans is protected by the bell of the Gomco clamp, injuries to the glans are rare. No parts are left on the penis, so late complications are rare compared to devices like the Plastibell which remain on the penis.

Care must be taken to ensure that the device is properly sterilized between procedures, or transmission of infection may occur. The American Academy of Pediatrics reviewed one study of 1,000 newborn Gomco circumcisions in a hospital setting in Saudi Arabia and rated it "fair evidence". The study found an overall complication rate of 1.9%. Bleeding occurred in 0.6% of cases, infection in 0.4%, and insufficient foreskin removed in 0.3%.