Abstract
The purpose of this study is to understand psychological determinants on trust in an involved party, degree of understanding information and acceptance of opinion from an involved party, concerning the future plan on the Daijyu-seki of the Yoshino river. The results of the questionnaire survey of Tokushima-citizens (545 responses and 20% response rate) were as follows. a) In the group of citizens with high interest, the main determinants was not procedural justice, but similarity of opinion between an involved party and themselves. In the group of citizens with low interest, the main determinants was not similarity of opinion between an involved party and themselves, but procedural justice. b) Main determinants of deeper understanding information relevant to future vision are similarity of opinion between an involved party and themselves, and ulilization of past experience as one's own. c) Citizenes have a tendency toward to accept the opinion of an involved party with the determinats on trust in an involved party and deeper understanding of the information, by opportunity of confirming about whole citizen's opinion.