The relationship between fishing, livelihood diversification and poverty was investigated in the lower Mekong basin, in Laos, where fishing forms an important, but usually secondary part of rural livelihoods. Results from a household survey show that participation in fishing is common and positively associated with higher occupational diversity and more agricultural activities. This is likely due to the low opportunity costs associated with many forms of fishing and factors such as tradition, enjoyment of fishing, underutilised labour and low capital requirements. Alternative livelihoods within the rural setting are therefore unlikely to cause fishers to leave the fishery, but instead strengthen the livelihood portfolio as a supplementary activity. Fishing is not an activity only for the very poorest households, but is undertaken by all wealth groups. However, fishing forms a greater proportion of income, employment and food security for the poor and is important in households with poor quality farm land.