Aim To examine the responsiveness and minimal important change (MIC) of two gait performance measures, the Functional Mobility Scale (FMS) and the Gillette Functional Assessment Questionnaire walking scale (FAQ), in a paediatric inpatient setting. Method Sixty-four children and adolescents with a motor disorder, including cerebral palsy, traumatic brain injury, or stroke (25 females, 39 males; mean age [SD] 12y 6mo [3y 2mo], range 6-18y 6mo), were recruited. Physiotherapists scored the FMS and FAQ at the start and end of active gait rehabilitation. Change scores were compared with changes in gait capacity tests, the walking item of the Functional Independence Measure for Children, and a global rating scale (GRS) on the physiotherapists' perceived change of the child's functional mobility. The GRS was also used to define the MIC. Results Change scores of the FMS and FAQ correlated between 0.35 and 0.49 with those of the capacity tests, 0.54 to 0.76 with the Functional Independence Measure for Children walking item change scores, and 0.57 to 0.76 with the GRS. The MIC values for the FMS and FAQ were 0.5 and 1.5 respectively. Interpretation FMS and FAQ can illustrate change in inpatient gait performance of children and adolescents with motor disorders. An improvement of one level in the FMS and two levels in the FAQ is considered as a clinically meaningful change.