Neurological soft-sign abnormalities have been implicated in obsessive-compulsive disorder (OCD). This first comprehensive data analysis evaluated the association between baseline neurological soft signs and treatment response in 117 OCD patients treated with controlled-release fluvoxamine in a double-blind placebo-con trolled trial. Total and right-sided soft signs for the responders and the nonresponders did not differ significantly. Left-sided visuospatial soft signs were significantly increased in treatment nonresponders compared to responders. These subtle neurological abnormalities may implicate a potential subgroup of OCD patients with poorer treatment response. This may have treatment implications and therefore serve as a screening tool in OCD.