The purpose of this research is to compare community histories, characteristics, factors and consequences of the economic, political, social and cultural changes in Yur, Thai Dum and Thai Lao communities. This study required field research work for a year. Both qualitative and quantitative techniques for collecting data were used. Results of the research determined that the three communities were similar as regards their cluster pattern of settlement, but each community has its own community history. The comparison of the characteristics of the economic change in the three communities was similar as regards occupation, labour exchange and employment, and economic way of life. The life styles have changed from self-sufficient economies to market economies. The comparison of the characteristics of the political change in the three communities is similar as regards the government having more roles in the communities and the villagers having improved their attitudes toward the government. The comparison of the change in the characteristics of the family and kinship systems differs in each community structure as regards the family patterns, parental roles, marriage and heritage. Although the kinship system has changed slowly, the kinship relationship in both Yur and Thai Lao communities was looser than in Thai Dum community. The comparison of the changes in the characteristics of the educational system are similar in the three communities as regards the social value for continuing education and teachers’ roles. The comparison of the change in the characteristics of the public health system are similar in the three communities as regards using western medicine. The comparison of the change in the characteristics of belief systems and customs differed in each community. In summary, the comparisons of the economic, political, social and cultural changes have been proved mostly in accordance with the hypotheses. The factors of ecology, ethnicity, experience and personality support these changes. These factors are interrelated and have the greatest influence on economic change and then on political, social and cultural changes, in that order. The comparison of the consequences of the economic change is similar in the three communities as regards using modern agricultural technology, increasing debt and good attitudes toward the economic status of the villagers. The comparison of the consequences of the political change is also similar in the three communities as regards self-confidence in the villagers’ opinions, and good relationships with government officials. The comparison of the consequences of social and cultural change is similar in the three communities as regards household facilities, quality of life, improved attitudes toward community development and government officials, assimilation, and community problems. No consequences influenced Buddhist beliefs and seniority. However, the degree of consequences differs in each community. Thus, the consequences of the economic change are greater than political, then social and then cultural changes in each community, in that order.