Neutering is a procedure used to "de-sex" an animal. This procedure has been used to control animal population growth, reduce unwanted sexual behavior in pets, and decrease or eliminate the possibility of certain disease conditions later in life, such as pyometra or infection in the uterus.

Castration is a term used to describe the removal of the gonads (testicles) in male animals. Spaying is a term used to describe the sterilization procedure of females. The procedure of spaying most often consists of removal of both the ovaries and uterus, which is called an ovariohysterectomy. Both procedures are performed under general anesthesia and both involve a surgical incision.

Neutering is done most commonly at or around six months of age. However, many veterinarians perform this procedure earlier – as early as 8 to 10 weeks in some situations. Early neutering can be done safely and has a number of advantages, especially in cases of pet adoption.