In 1997 Pet Sitters International (PSI) successfully campaigned to have “pet sitting” added to the Random House Dictionary. “Pet sitting” is defined as “the act of caring for a pet in its own home while the owner is away.” Dog walking is also a form of pet sitting since it involves coming to the pet’s home to provide exercise and companionship. Caring for pets in the clients’ homes is what separates pet sitters from boarders or doggie daycares. Pet sitters visit the pet home to provide a range of services. This primarily involves feeding, exercise and companionship. Pet sitters generally bill clients on a per-visit, per-day or per vacation basis, and include additional charges for multiple pets, travel expenses, and non-standard duties.