This study examined criterion-related validity and clinimetric properties of the Pediatric Motor Activity Log (PMAL) in children with cerebral palsy. Study participants were 41 children (age range: 28-113 months) and their parents. Criterion-related validity was evaluated by the associations between the PMAL and criterion measures at baseline and posttreatment, including the self-care, mobility, and cognition subscale, the total performance of the Functional Independence Measure in children (WeeFIM), and the grasping and visual-motor integration of the Peabody Developmental Motor Scales. Pearson correlation coefficients were calculated. Responsiveness was examined using the paired "t" test and the standardized response mean, the minimal detectable change was captured at the 90% confidence level, and the minimal clinically important change was estimated using anchor-based and distribution-based approaches. The PMAL-QOM showed fair concurrent validity at pretreatment and posttreatment and predictive validity, whereas the PMAL-AOU had fair concurrent validity at posttreatment only. The PMAL-AOU and PMAL-QOM were both markedly responsive to change after treatment. Improvement of at least 0.67 points on the PMAL-AOU and 0.66 points on the PMAL-QOM can be considered as a true change, not measurement error. A mean change has to exceed the range of 0.39-0.94 on the PMAL-AOU and the range of 0.38-0.74 on the PMAL-QOM to be regarded as clinically important change. (Contains 3 tables.)