OBJECTIVE To report use of ventriculoperitoneal shunt in dogs for management of hydrocephalus for which no cause could be identified. METHODS Case series. METHODS Dogs with hydrocephalus (n=12). METHODS Medical records (June 2003-June 2009) were reviewed to determine preoperative clinical findings, initial postoperative, and long-term outcome. Additional follow-up information was obtained from owners and referring veterinarians. RESULTS All dogs had signs of forebrain dysfunction, 7 had vestibular signs and 3 had signs of spinal pain. Postoperative complications included pain (n=4), undershunting because of shunt kinking (n=1) and seizures (n=1). Initial improvement occurred in all dogs and was sustained in 9 dogs, 1 of which required revision surgery. CONCLUSIONS Sustained clinical improvement can be achieved in hydrocephalus with no active underlying cause by use of ventriculoperitoneal shunting.