A skull mountable implantable percutaneous fluid delivery device (2； 52； 82； 02) is described for use in delivering fluids to target sites in the brain. The device (2； 52； 82； 102) includes a subcutaneous base portion (6； 56； 86) comprising one or more ports for supplying fluid to one or more implanted catheter devices (18). A percutaneous portion (4； 54； 84； 104) of the device comprises an extracorporeal surface (10), the one or more ports of the subcutaneous base portion (6； 56； 86； 106) being accessible from the extracorporeal surface (10) of the percutaneous portion(4； 54； 84； 104). The subcutaneous base portion (6； 56； 86) is at least partially insertable into a complementary recess formed in a bone (44； 140) and comprises one or more anchoring features comprising at least one radially protruding wing (24； 62； 88； 124) for directly anchoring the subcutaneous base portion (6； 56； 86；106) to the bone (44； 140).
