The objectives of this dissertation were 1) to study the factors affecting scout management in Basic Education Institutions, Pathum Thani province, 2) to develop an effectiveness model of scout management in Basic Education Institutions, Pathum Thani province, 3) to propose an effectiveness model of scout management in Basic Education Institutions, Pathum Thani province. Multiphase mixed methods research was designed by using quantitative methods to extend qualitative results. It was divided into 3 phases. Phase 1 qualitative research, the key informants where expert in scout management were selected by using purposive sampling of 12 key informants. Data were collected by interview form and were analyzed by using analytic induction. Phase 2 qualitative research, focus group discussion by a qualified person, namely the school scout director, Qualified Official Boy Scouts Specifically of 9experts were used, data were analyzed by content analysis. Phase 3 quantitative research, the questionnaire was used to validate the effectiveness model of scout management in Basic Education Institutions, Pathum Thani Province. The sample group was determined using a sample size of 10 persons per 1number of path showing the relationship between the variables in the model for all 62 paths.