How can we measure the impact of actions taken to improve the active offer of health and social services in French to francophone minority communities? A questionnaire was created to measure firstly individual behaviours of active offer and secondly the perception of organisational support toward it. Content validity of the Active Offer of French Language Services in Minority Context Measure was determined through a literature review, expert consultations and a Canada-wide Delphi survey. Reliability was examined with data collected from recent graduates in health and social services. The questionnaire shows good internal consistency and further studies with a larger sample are necessary to determine its temporal stability. These are the first steps toward measuring the development of active offer behaviours following educational or organisational change activities that favour French-language services. It is also likely to help researchers study the determinants of such behaviours.