As part of being a responsible pet owner, there comes a time when you must help your pet along its path. This decision is not always easy, but your cat's dignity, balanced with the reasonable care you can expect to provide, help provide guidance as you weigh your options.
Instructions
Consider your cat's health. As part of a routine checkup, your vet may discover tumors or other conditions that require veterinary intervention. Balance the intervention against your cat's general health. Too aggressive an intervention on an elderly, frail cat may not provide the quality of life to which your cat is accustomed.
Balance what you can give against what is required. If you will need to supervise your cat during the day, but work full time outside of the home or are managing the needs of an active family, it may not be reasonable to expect that you can provide supervision on a long term basis.
Be aware of your cat's needs. If your cat is beginning to lose muscle control due to arthritis and you're seeing an increase in accidents around the house, then your cat may be suffering. Cats are fastidious, tidy creatures and need to be able to function in this fashion.
Talk to your vet. An accident may be the sign of an infection, not a muscular or arthritic issue. Work with your vet to best use their knowledge to improve your cat's quality of life.
Know when to let go. As hard as it is, part of the responsibility you take on with a kitten is the responsibility to end your cat's life if it's their time. Respect the limits of what modern veterinary medicine can do, what you can do and what your cat requires.