Irrigation infrastructure expansion threatens the diversity of freshwater fish worldwide. Irrigation infrastructure creates migration barriers which can block access to important nursery, feeding and spawning habitat. Lao PDR is a landlocked country situated within the Lower Mekong River Basin where there is a substantial dependency on rice and fish for food, income and livelihoods. The country is experiencing an unprecedented boom in irrigation infrastructure investment, with modernisation programs being implemented in every province. Despite significant investment in infrastructure upgrades, and the potential impact on freshwater fish, little consideration has been given to fish passage solutions. In 2008, we commenced a fish passage program in Lao PDR. The intent of this case study is to outline the pivotal elements of the program of knowledge development and transfer, in the context of river connectivity and fisheries management in Lao PDR. We also highlight challenges in international research in development and lessons learned.