Since 1990s to date, there has been a growing global interest among researchers in impact assessment of research and development (R&D). Attention has specifically been placed on the impact of R&D interventions on target beneficiaries. In this regard, this work, besides reviewing studies on impact assessment of agricultural research in Tanzania it documents the experience of Tanzanian farmers in the use of innovations by focusing on rice research-based innovations. Adaptation rather than adoption of innovations is evident in smallholder rice farming. Moreover, it sheds light on the limitation...