Abstract This article reviews the changes undergone by CIAT (the International Centre for Tropical Agriculture) in order to enable itself to address concerns about the sustainability of agricultural production. From its foundation, CIAT was mandated to conduct research that would promote agricultural improvement in Latin America. This work was initially focused upon the improvement of a range of discrete commodities that were important to the region served, and was conducted in a manner consistent with the `linear' model of innovation. Gradually, CIAT's management and staff realised that environmental degradation threatened the long-term success of agriculture in the region. Many such problems transcend the boundaries between study of different commodities and thus become apparent at the level of larger-scale systems, of which individual commodities are merely components. To address these problems, then, it is necessary to conduct research at a level of complexity higher than that of the discrete commodity. CIAT's organisation therefore changed to include units that operated at a level of complexity appropriate to the problems under consideration. It is argued that these changes contradicted many of the prescriptions of the `linear' model, and thus represented movement towards a new professional practice consistent with Rothwell's “fifth generation” model of innovation.