Many studies have examined the particular farm-level factors affecting the adoption of new technologies by smallholders. Using an ‘actor-oriented perspective’, this paper focuses on the larger processes at work in the development, dissemination and adoption of improved technologies. Three case studies of upland soil conservation projects in the Philippines are used to illustrate the argument that successful adoption depends on more than careful planning in research and the use of appropriate methodologies in extension. It depends on the timely formation of coalitions of key actors whose interests converge sufficiently that they can focus their resources and efforts on achieving change in agricultural systems. It also depends on critical external factors that are largely unpredictable. Newer approaches such as ‘participatory technology development’ are based on an appreciation of the evolving, adaptive and inherently participative nature of agricultural development processes. However, a broader, more flexible approach is needed which gives explicit recognition to the personal, cultural and political dimensions of coalition-building for technology development.