Efforts to unlock the genetic potential of both rice and fish, when combined with improvements in the management of rice-fish systems, can potentially increase agricultural productivity and food security in some of the poorest and most populous countries in Asia. In Bangladesh, estimates suggest that the country’s potential rice-fish production system encompasses 2–3 million hectares of land. But despite three decades of research on biophysical and technical aspects of rice-fish systems, this potential has not been fully realized due to insufficient attention given to the social, economic, and policy dimensions of rice-fish system improvement. This paper provides a characterization of the diverse and changing nature of rice-fish systems in Bangladesh to shed new light on the economic viability of different rice-fish systems and recommend policy and investment options to accelerate the development of appropriate rice–fish technologies.