Despite the wider acceptance of gamification approaches to design and innovation, researchers have not extensively considered the link between gamification and cocreation. This paper aims to research the main impacts of gamification approaches to codesign, i.e. interaction and interchange of ideas between users/customers, suppliers and designers in the development of new solutions. In order to better understand this complex relationship, case studies with selected firms, participating in an on-going co-creation project, have been conducted through the deployment of a gamified method and tool and a combination of different instruments, as workshops and interviews. Grounded theory was the inductive methodology adopted for these qualitative case studies, which is in line with the goal of building theory. Besides contributions to clarify the relationship between co-creation and gamification, this paper provides key implications for managers on how to generate innovative concepts through interaction with customers and other key stakeholders in a gamified environment. This paper illustrates how gamification approach to co-design has facilitated collaboration between team members with different backgrounds and interests, increased stakeholders engagement in the process, offered collective creativity experiences and delivered a clear output and thus increased the probability of having a successful concept at the end of the project.