In this work, 140 patients with hydrocephalus associated with posterior fossa tumours are studied, comparing the different ways of treating hydrocephalus naming: V-P shunt placement before tumour excision, direct tumour excision without CSF diversion, endoscopic third ventriculostomy and fixation of an external ventricular drain during surgery to remain as an ICP monitor for few days postoperatively. The aim of the work is to determine the best protocol for management of hydrocephalus in posterior fossa tumour patients.