Abstract
This study aimed to clarify the relationship between ‘outsider effect’ and residents' behavior change in regional development by applying the transtheoretical model of health behavior change. The qualitative research in the case study in Suttsu of Hokkaido illustrated the behavior change of local residents' initiative. Outsider can provide effectively chances and places for residents' participation. For the sustainable stage of local development, they need diverse approaches for fun depending on individual interest and lifestyle, rather than concentration on regional social problems. The role of local coordinator is also indispensable for the networking the community.