Qualitative comparative analysis is increasingly popular as a methodological option in the evaluator’s toolkit. However, evaluators who are willing to apply it face inconsistent suggestions regarding the choice of the "solution term". These inconsistent suggestions reflect a current broad debate among proponents of two approaches to qualitative comparative analysis. The first approach focuses on substantial interpretability and the second on redundancy-free results. We offer three questions to guide the choice of a solution term in the context of impact multi-method evaluation research. They are related to the intended use of the findings, goals of the analysis and regularity theory of causality. Finally, we showcase guidelines through three potential applications of qualitative comparative analysis. The guiding questions would almost always lead to choosing the substantial interpretability approach. However, the redundancy-free approach should not be disregarded. Whatever the choice, researchers should be aware of the assumptions each approach is based on and the risks involved.