Objectives To determine if Cognitive Orientation to Occupational Performance was effective in improving performance and transfer of motor learning in children with developmental coordination disorder (with/without attention deficit hyperactivity disorder); and whether outcomes were maintained three months post-intervention. Design Randomized waitlist-control trial (ClinicalTrials.gov ID: NCT02597751) Setting BC Children's Hospital, Vancouver, Canada Subjects Thirty-seven children with developmental coordination disorder and 41 children with co-occurring attention deficit hyperactivity disorder (all 8–12 years), randomized to treatment or waitlist groups. Interventions One-hour of intervention once weekly for 10 weeks. Main Measures (1) Canadian Occupational Performance Measure to measure self-perceived performance of motor goals (10-point scale); (2) Performance Quality Rating Scale to measure therapist-observed movement quality (10-point scale); and (3) Bruininks-Oseretsky Test of Motor Proficiency – 2nd ed. to measure overall motor skill ability/transfer of motor learning (percentile). Results Both groups showed significant improvement ( p < 0.001) in motor performance (developmental coordination disorder: pre: 2.7 ± 2.2, post: 7.0 ± 1.0; developmental coordination disorder with attention deficit hyperactivity disorder: pre: 2.3 ± 1.7, post: 7.0 ± 1.5) and movement quality (developmental coordination disorder: pre: 3.0 ± 1.5, post: 6.3 ± 1.7; developmental coordination disorder with attention deficit hyperactivity disorder: pre: 3.0 ± 1.9, post: 5.7 ± 2.3). Three months after treatment, children maintained their gains, but only children with developmental coordination disorder showed transfer of learning to overall motor skills (pre:12 ± 15, post:12 ± 12, follow-up:14 ± 20, p < 0.001). Conclusion Intervention was similarly effective for children with developmental coordination disorder with/without attention deficit hyperactivity disorder in achieving and maintaining functional motor goals, but only children with developmental coordination disorder showed transfer of learning to other motor skills.