Our current ability to identify and appropriately treat infants who are at risk for developing various handicapping conditions is limited. Thus, research aimed at developing early diagnostic techniques and differential intervention programs for infants at risk for handicaps needs further attention. The purpose of this study was to determine if infants who suffered perinatal intraventricular hemorrhage and who received routine medical care plus sensorimotor intervention between 3 and 12 months of age, differed from similar infants who received only routine medical care. Twenty-four subjects (10 experimental and 14 control) who were patients in neonatal intensive care at University of Utah or Primary Children's Medical Centers constituted the study sample. Descriptive data specific to the birth and perinatal period were obtained on the infant and its mother. All infants were evaluated with the Battelle Developmental Inventory at 3 and 12-months corrected age. In addition, the Carey Infant Temperament Questionnaire was completed by the parent when the infant was 6 to 9 months corrected age, and the Parenting Stress Index was completed when the infants was 12 months corrected age. Experimental subjects and their parent(s) participated in an individualized sensorimotor intervention program, directed by a licensed physical therapist, for 1 hour per week on a bi-monthly basis. Parents reported spending an average of 20 minutes per day, 5 days per week, working on exercises with their infant at home throughout the 9- month program. A statistically significant positive relationship was found between developmental outcome and participation in sensorimotor intervention , as measured by the posttest Battelle. No significant differences between groups were found on levels of parenting stress. On each of the measures, stress levels were moderate. Continued enrollment and annual follow-up of subjects in the current study will allow for longitudinal evaluation of the effects of early sensorimotor intervention on development.