There isn't much difference between a pet sitter and a baby sitter. Pet sitters are hired to care and take responsibility for your animal in your home while you're away. This can be a simple or complicated task -- it all depends on your pet.
The main responsibilities of a pet sitter are fairly obvious: They should provide your pet with food and opportunities to go to the bathroom, whether this requires taking it for a walk, cleaning its litter box or cleaning its cage. It's your responsibility to ensure that you have enough food and bathroom materials at home for the duration of your trip.
One of the biggest advantages to hiring a pet sitter is that your pet can keep its day-to-day routine while you're gone [source: Pet Sitters]. Therefore, the pet sitter should keep your pet on that routine. If you play with your animal every day at 6 p.m., your sitter should do the same. However, it's your duty to make sure your sitter's aware of your pet's regular schedule so he or she can make the proper arrangements. Typed lists are very effective.
The pet sitter is responsible for seeking out proper care for your animal in the event of a medical emergency. You should make sure he or she knows where your veterinarian is located and how to reach him or her. It's also a good idea to leave a sitter with the phone numbers of emergency centers that can treat your pet outside of normal business hours. Again, a typed list is very effective here.
Beyond those responsibilities, a pet sitter also should give your animal love and attention. Some pet sitters may be willing to take over some house-sitting responsibilities as well, such as checking the mail or watering the plants. This varies between sitters and is likely to cost extra.