This study describes the research approach adopted to identify population dynamics and livelihood changes in small-scall communities in rural Laos, and what research results were obtained as a result of the study. A diet survey based on a two and a half years’ food diary in a swidden agriculture community in central Laos provided a valuable record of residents’ dietary habits in a rapidly developing frontier region of Southeast Asia. Furthermore, the time allocation survey focused on daily life, which is vulnerable to the influence of market economization, and clarified the subsistence structure. In a village near the Thai border in central Laos, a retrospective survey was conducted to clarify the population dynamics from the establishment of the village to the present day, and the population dynamics and livelihood changes in rural Laos were clarified in light of the impact of migrant workers to Thailand. In the area of mixed ethnic groups in northern Laos, we clarified the problems of livelihood change caused by internal resettlement from the highlands to the basin, based on the possibility of acquiring agricultural land and the actual situation of migrant workers. In each of these areas, the research perspective of household reproduction as it relates to population dynamics was incorporated to discuss future issues in research on small-scall communities.