Horses come to rescue or adoption agencies through several means. Some horses are unwanted — either they have grown old or their owners lost interest in them. Some horses have temperament problems that make them impossible to handle; this may be due to bad breeding, incorrect training or cruel treatment. Whatever the cause, some horses require extensive retraining in order to be ridden or worked.
Rescues may take place at homes or farms where horses are being ill-treated, or horses may be brought to the agency by people who can no longer care for their horse but hope that someone else will. In a worst-case scenario, some people send their horses to a rescue center because they have tried to sell the animal and its health or temperament has made it unsalable.