Imaging studies, particularly magnetic resonance (MR) imaging, can be extremely helpful in cerebral palsy. Both the cause of insult and the age of the fetus at the time of the insult are important factors in determining the signal intensity and pattern of abnormality detected on MR imaging. As a result, MR studies can provide information regarding both the cause and timing of the cerebral damage or malformation. Additionally, MR studies are capable of determining the extent or severity of cerebral involvement, which can affect prognosis. This article presents imaging findings associated with the most common causes of cerebral palsy. MRDD Research Reviews 3:118-128, 1997. © 1997 Wiley-Liss, Inc.