A common question for veterinarians is what to do when a litter box-trained cat suddenly starts urinating and/or defecating outside of the litterbox. Urinating outside of the box is the most common complaint. This is a question without a quick, easy answer. A common question for veterinarians is what to do when a litter box-trained cat suddenly starts urinating and/or defecating outside of the litterbox. Urinating outside of the box is the most common complaint. This is a question without a quick, easy answer. Many factors have to be looked in order to accurately answer this question. First and foremost: is this a medical problem, or a behavioral one? An examination of your cat and a lab analysis on the urine by your vet will help determine the proper course of action. The purpose of this article is to help the pet owner develop observational skills to help determine why Fluffy isn't going to the litterbox. How is the general health of your cat? Have you noticed any changes in appetite, thirst, frequency of going to the litter box? Has your cat recently recovered from illness or surgery? If your cat associates the litter box with pain in any way, s/he may avoid the box even after the initial pain/difficulty has passed. Where is the litter box located? Cats prefer privacy and quiet -- a litter box in a high-traffic, noisy location may be avoided in search of quieter locales. Cats also don't like to sleep or eat near the litter box. Does your cat have fresh water and a high-quality diet? Fresh water should be available at all times, and your cat should be on a high-quality maintenance diet appropriate for age/weight. Special urinary diets are available, but should be only used under the advice of a veterinarian. Is your cat neutered*? Non-neutered cats will tend to urine mark their territory more than neutered cats, thus neutering will reduce urine marking. However, all cats can urine mark, including females. (*neutered = castrated males, spayed females) Is your cat exhibiting excessive licking of the genital area? Urinary tract infections can be painful, burning, and even cause blockage in male cats. (NOTE: urinary blockage is a life-threatening condition - if you cat is unable to produce urine, see a veterinarian immediately.) Have you caught your cat 'in the act' of voiding outside of the box? If so, take note of your cat's posture while voiding -- is your cat is backing up to vertical surfaces, such as walls or furniture and voiding (a.k.a. spraying) or assuming a more 'natural' squat position? The former may be more indicative of a behavioral marking problem. Has the litter or litter box been changed lately? Assuming that your litter box cleaning/maintenance schedule was previously acceptable for your cat, has the brand of litter been changed or the type of box different (i.e. hooded box vs. open)? Cats often have a preference for a litter and box type - changing this may invite behavioral problems. What is the cat to litter box ratio? As a general rule of thumb, it is good to have one litter box per 1-2 cats, and clean the litter boxes at least once daily. Has there been anything or anyone new in your house? Changes such as house guests, a new baby, remodeling, or a new pet can stress your cat. In some cats, this is obvious - hiding or skittish behavior. In other cats, they may not appear outwardly stressed, but may void urine out of the box to show their disapproval -- for example, urinating on your house guest's shoes. Stress and not voiding as often as usual can also lead to a bladder infection. Feline urinary behavior and medical problems are complex topics. Contact your veterinarian if any changes in litter box habits are noted.