International civil society and non-government organisations (NGOs) play a role in implementing agricultural projects, which contribute to the mitigation, adaptation, and food security dimensions of climate-smart agriculture (CSA). Despite the growth of CSA, it remains unclear how CSA is designed, conceptualised, and embedded into agricultural development projects led and implemented by NGOs, creating a lack of clarity as to the direction of future of agricultural development interventions. This paper examines the extent to which development programmes from the NGO sector actively incorporate CSA principles to benefit smallholder farmers under the major pillars of CSA. Drawing from six projects’ documentation since 2009, we conducted a thematic analysis to reveal the alignment of projects with the pillars of CSA and discuss the extent to which CSA allows for localised adaptability given the diverse agricultural contexts in which civil society and NGOs work. We find that despite a lack of clarity in CSA definition and focus, the agricultural practices in the six projects make heterogenous contributions to the adoption of CSA principles. We illustrate the diversity of ways in which CSA is ‘done’ by a global NGO across six areas: greening and forests, practices and knowledge exchange, markets, policy and institutions, nutrition, carbon and climate, and gender. We discuss the need for balance in contextual adaptability across the three pillars of CSA with explicit consideration of trade-offs to reduce unintended outcomes from CSA initiatives. We conclude with reflections on the role of civil society and NGOs as boundary agents in the agricultural development sector.