In this paper, we examine the impact of Future Design (FD) on public workshops organized in Matsumoto city, Japan, for its city hall renovation plan. We ran an FD workshop and an ordinary workshop as a control, and the participants were randomly assigned to one of the two workshops. We identified the SVO (social value orientation) type (pro-social, pro-self, and other) and elicited time preference of each participant using simple questionnaires that were independent of the context of the workshops. We found that pro-self individuals tend to have shorter time perspectives than pro-social individuals before the workshops. While the pro-self individuals who went through the ordinary workshop became even more myopic, we did not detect such adverse effects in the FD workshop. This contrast between the ordinary and FD workshops is consistent with the qualitative differences in the policy outcomes between the two workshops. The discussions in the ordinary workshop tended to focus on the resolution of today’s needs, such as acquiring more rooms and more services, etc., while the discussions in the FD workshop focused on the more fundamental functions of the city hall that will be needed in the future, thereby leading to more constructive policy proposals. Such demand-based discussions in the ordinary workshop may have been a result of the growing myopia within the pro-self participants, who insisted on ensuring their current needs.