The aim of this study is to get the guidelines of opening the public facilities. The guidelines have been obtained from the process of forming the open-space inside the public assembly facilities and from analyzing its present state. Through the analysis of the developing process of the towns and the assembly facilities since the cultivation period of Hokkaido, this study has made it clear that the role of the open-space inside the facilities has been changing all the time. By the examination of the facilities which has been built up since 1980 and is more than 1000m^2 in area, the present state of the open-space inside the facilities will be gained. The study has proved that the open-space inside the facilities has an important role that even a single person has a possibility to use them. The conclusion of this study is that this role has enabled a person as well as a group to use the facilities. As a result, assembly halls, lobbies, display-rooms, Japanese-rooms, traffic-spaces can be selected as the elements of the open-space inside the facilities. These elements have a close relation to the designer's intention, HAKIKAE-line and Served Space and Serving Space.
