Sixteen of 26 hand-reared kakapo chicks (62%) have been successfully returned to the wild. These chicks were initially kept in thermostatically-controlled brooders, then in plastic tubs in an air-conditioned room, and finally a pen in an unheated room prior to transfer to an outdoor pen and release in the wild. Brooding temperature was progressively reduced to simulate the progressively longer period kakapo chicks spend in the nest without brooding. Humidity was maintained at 80% to simulate that measured in kakapo nests. Some chicks fed a relatively high fat diet within their first 20 days after hatching developed fatty liver disease; subsequently, chicks less than 45 days of age were fed a lower fat diet and older chicks gradually converted to a higher fat diet. Normal gut flora was successfully established in chicks by adding small quantities of adult kakapo faeces that had been screened for diseases and parasites. The growth rate of hand-reared chicks was significantly slower than that of parent-reared chicks during the first 40 days after hatching but there was no significant difference in growth rate in older chicks. Half the disparity in the growth rates of hand-reared and parent-reared chicks was due to the fact that most hand-reared chicks were suffering from ill health or injury before being taken into captivity. Two male chicks reared in isolation from other kakapo display varying degrees of sexual attraction to humans. The only sexually mature hand-reared female chick has mated and hatched a chick in the wild. Hand-reared kakapo comprised 40% of all chicks fledged since 1990 and presently comprise 20% of the total population of 86 birds.