TNR: What is it?

TNR stands for "Trap, Neuter, Return"

TNR is an accepted practice recommended by all humane organizations to control the stray and feral cat population.

Cats are caught in a humane trap.
Females are "spayed" and males are "neutered" by a veterinarian.
(females should be allowed several days to recover) 
and then returned to their original environment.

Note: Cats are "returned", not to be confused with "released". 
Advocates recommend returning the cat to the location he/she was caught and is familiar with, for the best chance of survival.