Developing and institutionalizing cross-sectoral approaches to sustainable land use remains a crucial, yet politically contested, objective in global sustainability governance. There is a widely acknowledged need for more integrated approaches to sustainable land use that reconcile multiple landscape functions, sectors and stakeholders. However, this faces a number of challenges in practice, including the lack of policy coherence and institutional conflicts across agricultural and forest sectors. In this context, the global climate change mitigation mechanism of “reducing emissions from deforestation and forest degradation” (REDD+) has been flagged as a unique opportunity to stimulate the development and institutionalization of more integrated, “landscape” approaches to sustainable land use. In this article, we provide a reality check for the prospects of REDD+ to deliver on this promise, through analyzing three pioneer cases of REDD+ development and implementation in Brazil, Ecuador, and Mexico. We analyze how REDD+ has operated in each of these three contexts, based on field work, key-informant interviews, and analysis of primary and secondary documents. Our findings suggest that REDD+ has stimulated development of “niche” sustainable land-use investments in each case, which aim to integrate forest conservation and agricultural development goals, but has done so while competing with business-as-usual incentives. We conclude that national and international political commitment to more integrated and sustainable land-use approaches is a precondition for, rather than a result of, transformative REDD+ interventions.