In this Think Piece we argue that mental health system reforms are not mainly driven by scientific evidence and international standards, but rather by concrete political constellations, national and international development agendas, local and global socioeconomic contexts, and the interactions between differently positioned actors. We further argue that these forces gain their influence not by being openly discussed, but precisely because they are rendered invisible and turned into what Geissler (2013) calls ‘unknown knowns’. To illustrate these complex processes, we present a case study that examines how mental health system reform processes in the West Bank are shaped by the Israeli occupation, particular political events, and unequal power relations between international and local institutional actors. Furthermore, we present critical reflections by mental health providers related to these processes, and their visions for a more sustainable mental health system. We end with an appeal to aid providers to stop characterising their work with abstract catchphrases such as ‘evidence-based’ or ‘best practice’, and call on them to be transparent about how political, economic, and social contexts shape their work on the ground.