Objective: To identify and critically appraise clinical measurement tools used to assess sitting posture, seated postural control or functional abilities for children with motor impairment who are candidates for seating interventions. Data sources: Searches were run in 15 electronic databases along with hand searching. The search included articles published in English to December 2011. Review methods: Key terms included: posture, sitting, sitting posture, seated posture, seated postural control, sitting position, seating, wheelchair(s), outcome and assess(ment). The PRISMA statement was followed with inclusion criteria set a priori. Two reviewers independently screened titles, reviewed abstracts and identified full-text articles that met criteria. Data extraction included tool description and clinical utility. Two quality-rating scales were used to evaluate conduct of the studies and psychometric properties of the tools. Results: Of the 497 titles found in the search, 29 full-text articles met the inclusion criteria and 19 tools were identified. Tools represented all components of the International Classification of Functioning, Disability and Health for Children and Youth (ICF-CY), with emphasis on body structure and function and activity components. Evidence supporting reliability and validity varied, with small sample sizes influencing quality ratings. Evidence of the tools’ reliability was more prevalent than evidence of the tools’ validity. Only four tools reported on responsiveness, an important consideration for evaluating change. Little information on clinical utility was provided. Conclusion: Although a number of tools are available, evidence supporting their use for seating interventions is limited, as is the evidence supporting the strength of their measurement properties. Few tools address participation, environmental factors or the child’s and family’s perspective.