As of July 2017, the boards of all the major national veterinary organizations have endorsed this practice:
- The American Veterinary Medical Association
- Association American Animal Hospital Association
- American Association of Feline Practitioners
- Association of Shelter Veterinarians
- Catalyst Council
Other cat-related organizations have also endorsed the Feline Fix by Five initiative. They include:
- WINN Feline Foundation
- United Spay Alliance
- The Cat Fanciers’ Association
- The International Cat Association.
Several national veterinary organizations (AVMA, AAHA, AAFP, ASV, ) have endorsed the idea of sterilization of cats prior to first heat. The statement which they endorsed can be found here.