The large number of available physical activity (PA) questionnaires makes it difficult to select the most appropriate questionnaire for a certain purpose. This choice is further hampered by incomplete reporting and unsatisfactory evaluation of the content and measurement properties of the questionnaires. We provide a checklist for appraising the qualitative attributes and measurement properties of PA questionnaires, as a tool for selecting the most appropriate PA questionnaire for a certain target population and purpose. The checklist is called the Quality Assessment of Physical Activity Questionnaire (QAPAQ). This review is one of a group of four reviews in this issue of Sports Medicine on the content and measurement properties of physical activity questionnaires. Part 1 of the checklist can be used to appraise the qualitative attributes of PA questionnaires, i.e. the construct to be measured by the questionnaire, the purpose and target population for which it was developed, the format, interpretability and ease of use. Part 2 of the checklist can be used to appraise the measurement properties of a PA questionnaire, i.e. reliability (parameters of measurement error and reliability coefficients), validity (face and content validity, criterion validity and construct validity) and responsiveness. The QAPAQ can be used to select the most appropriate PA questionnaire for a certain purpose, but it can also be used to design or report a study on measurement properties of PA questionnaires. Using such a checklist will contribute to improving the assessment, reporting and appraisal of the content and measurement properties of PA questionnaires.