Eighteen cases are reported in which the myelographic appearances of adhesive arachnoiditis were found. These patients have had intrathecal steroid injections as either the only procedure or the most likely procedure that could have induced such changes. Adhesive arachnoiditis has not been found at this hospital in the absence of some type of intervention. Other possible iatrogenic causes of arachnoiditis have been excluded in this group. The literature on the aetiology and symptomatology of steroid-induced arachnoiditis is reviewed.