Integrating horizontal perspectives in sectoral policies is an increasingly popular way to address complex, societal problems like climate change and gender inequality. Policy evaluation can contribute to policy integration by shedding light on the coherence between sectoral goals and the mitigation or solution of the problem in question - including possible synergies and/or conflicts. To denote this evaluation modality, we introduce the concept of "integrated evaluation" - i.e. integrating horizontal perspectives in evaluations of sectoral policies. A Swedish case study helps identify salient factors affecting the implementation of this type of evaluation. We find that the prospect for integrated evaluation is significantly affected by the perceived inappropriateness in asking independent evaluators to contribute to political agendas, the lack of requisite knowledge to produce credible integrated evaluations, and a disinterest in the integrated perspective among policymakers. In light of our case study, we discuss the outlook for this kind of evaluation and provide ideas on how to support its future implementation.