This paper is intended to identify issues of concept design in a team, and in order to address the issues,proposing a framework for concept design in a team (FCDT). Teams inexperienced in concept design are often unable to design a quality concept within a relatively short time and through a visualized process. There is however a dearth of literature on such issues.This study started with identifying and categorizing issues of concept design, based on the literature survey and As-Is analysis. The issues included that 1) Team members inexperienced in concept design are not aware of the to-dos in concept design; 2) Team members inexperienced in concept design are not aware of how to consider the to-dos; 3) Team members inexperienced in concept design are not aware of the tools they could use for how to consider the todos identified in 2); 4) Team members inexperienced in concept design are unable to improve the quality of their Concept. A Concept is defined as the output of concept design.In order to address the issues, this study developed FCDT by creating a use case description based on context analysis and Checklands Soft Systems Methodology.Subsequently, this study evaluated, in 10 FCDT-based workshops and questionnaires to the participants after the workshop, the effectiveness of FCDT to address the aforementioned issues. One-day workshop was developed to help the inexperienced team members design a new business concept in a team. 43 teams of 223 employees from eight Japanese conglomerates in total participated in the workshops.The results suggested that FCDT was effective, in descriptive study, for addressing four issues in concept design in a team. This paper concludes with principal issues and areas of future research.