Combining insights from literature on the Theory of Change, Impact Evaluation, and Wellbeing, we develop a novel approach to assessing impacts. Intended beneficiaries identify and rate factors that are important to their wellbeing, their satisfaction with those factors now, and before an intervention. Qualitative responses to questions about perceived changes and causes of change are linked to quantitative data to draw inferences about the existence and/or importance of impact(s). We use data from 67 Ewamian people, in a case study relating to Indigenous land management, to provide proof of concept. 'Knowing that country is being looked after' and 'Having legal right/access to the country' were identified as important to wellbeing, with perceptions that Native Title determination, declared Indigenous Protected Area and associated land management programs have had a significant and positive impact on them. Further method testing might determine the utility of this approach in a wide range of settings.
Keywords: Impact evaluation; Indigenous land management; Life satisfaction; Monitoring and evaluation; Subjective wellbeing; Theory of Change.