Eight patients in which the Harrington instrumentation had to be removed are presented. In four patients a hook had dislocated, two further cases were due to infection, and in two cases the rod was too long causing discomfort in the neck. The removal was difficult in two cases because both hooks had become firmly anchored. In two subsequent cases we therefore used a high-speed drill mounted with a diamond disc to cut the Harrington rod thus facilitating the removal of the hooks and rod. Technical errors in insertion of the Harrington device are discussed.