The capability approach as a contribution to evaluating and strengthening social work practices. Strong Work! is a practical study for and with first-line social work. We want to contribute to the demand in the work field in order to understand, account for, make visible and comprehensible our own practice. At a time when social work benefits from understanding and showing what works, there is a need for new ideas and insights to visualise, substantiate and evaluate practices. The research starts from the premise that the Capability approach – as a scientifically based framework in which human development is central – can offer a valuable perspective to respond to this need.