AbstractRecently, there emerged a theory of collective psychological ownership – an intersubjective sense of possession for different objects within the work and organizational context (e.g., work space). This shared mind-set has been cast as having the potential to explain a variety of collective, work-related attitudes, and actions. Preventing scientific inquiry into this phenomenon is the absence of an instrument for the measurement of this construct. The purpose of this work was the development and validation of such an instrument. To this end, work with a panel of judges and three sequentially conducted field studies was undertaken. Construct validation evidence (e.g., content, discriminant, nomological, and incremental validity) for an instrument for the assessment of collective psychological ownership is provided.