A mandatory spaying/neutering law is the most humane solution to our overpopulation problem and makes sense economically.  Owners should be required to spay/neuter their cats and dogs unless they have a license to breed.  Spaying and neutering are routine, affordable and safe procedures.  According to numerous humane society and animal control organizations, in just six years, one unaltered female dog and her offspring can produce 67,000 puppies. In seven years, one female cat and her offspring can produce 370,000 kittens.  This leads to the birth of countless animals who will never find the loving home they deserve - instead, they will wonder the streets or end up in animal shelters where many (60% of dogs and 70% of cats, according to the ASPCA) will be euthanized for lack of a loving home.  The government operates countless animal shelters across the country through animal control departments.  Millions of taxpayer dollars are spent each year rounding up, sheltering and feeding, and euthanizing stray or unwanted animals.  It costs far less to spay/neuter an animal than it does to deal with the consequences of overpopulation and is a much more humane approach.