Birds of prey are increasingly popular. Unfortunately, this can also lead to unwanted problems. On 7 August 2011 a first calendar-­year female Sparrowhawk Accipiter nisus was admitted at the bird rehabilitation centre Vogelklas Karel Schot in Rotterdam. She had been found in an urban backyard with severely damaged and shortened flight feathers. Suspecting illegal removal from a nest and disastrous handling and keeping, a police investigation was undertaken but to no avail. The hawk was undernourished (198 g) but otherwise in good health. The centre provided housing and food for con­valescence. After the first moult, the plumage was again in good order, enabling specialised flight training by a falconer. After 22 months, the Sparrowhawk was measured, weighed (240 g) and ringed, and subsequently released in suitable habitat. Possible causes of this mysterious case are discussed. Feather abnormalities, like fright moult, French moult and pinching-­off syndrome are dismissed because – when found -­ the calamus was undamaged and fault bars were absent. Furthermore, the successful moult goes against the assumption of a medical cause. The pattern of feather damage strongly indicated poor housing in a small cage, possibly a parrot cage. In past years, the rehabilitation centre has seen and treated similar cases in other small raptor species like Kestrel Falco tinnunculus and Lesser Kestrel F. naumanni. (Illegal) keeping of raptors is a growing problem, hence a great need of better education.