When pet owners leave town for work or vacation, they need someone to keep an eye on their furry friends. Pet sitters usually take care of household pets at the pet's home until its owner returns, though some pet sitters bring the animals to their own home for the duration of the job when allowed by the owner. Responsibilities include visiting the pet, replenishing food and water supplies, cleaning the pet's living space, and playing with it. The most common pets are dogs and cats. Dogs need to be walked for exercise, and cats need play time to release energy.