Current investments in preventive lifestyle interventions are relatively low, despite the significant impact of unhealthy behaviour on population health. This raises the question of whether the criteria used in reimbursement decisions about healthcare interventions put preventive interventions at a disadvantage. In this paper, we highlight the decision-making framework used in the Netherlands to delineate the basic benefits package. Important criteria in that framework are ‘necessity’ and ‘cost-effectiveness’. Several normative choices need to be made, and these choices can have an important impact on the evaluation of lifestyle interventions, especially when making these criteria operational and quantifiable. Moreover, the implementation of the decision-making framework may prove to be difficult for lifestyle interventions. Improvements of the decision-making framework in the Netherlands are required to guarantee sound evaluations of lifestyle interventions aimed at improving health.