Since 1964 the author, who is Game Warden of Sabah (formerly British North Borneo) has been running a state-supported orang utan rehabilitation project in the Sepilok Forest Reserve. Most are confiscated animals, having been kept illegally, often as pets, and he describes some of the difficulties in getting them to become independent again and able to live in the forest. Some have even been too well treated in captivity, living luxuriously and treated like humans.