Research laboratories, universities and consulting firms undertake research activities for performances analysis, businesses, technologies, products and services developments, governments, and political and sociological systems developments. In the case of firms' studies, the key informants regarding any research are the firms' managers that are involved either through interviews, or ethnographies or questionnaires responses. The key informants provide many types of data for the development of research and their role is primordial in its on-going process. In the process of data collection, there can be some challenges and obstacles slowing down the move toward data analysis for the confirmation of the hypothesis of the research or the achievement of the research output. Thus, the aim of this paper is to investigate on the factors that can slow down the on-going process of any research while communicating with the managers for their research participation. The 'Deja Vu' research method derived from the research and used is based on the analysis of the interactions taking place among university's researchers and firms' managers in the automotive and aerospace industry. The initial purposes of these interactions were for action research for businesses analysis and development and case studies creation from the firms for action learning of an international master program students. The paper presents the 'Deja Vu' research method' and provides details and definitions of the factors' constraints with respect to the firm's managers research participation. We find out that both actions -research and learning-have common factors' constraints as the managers availability and managers' strategic position in the firms, and different factors regarding the implications as value-added to business development and financial funds, and the brand image and the financial support for learning, respectively. And according to the types of actions and based on the factors' constraints, we derive a brief methodology for researchers to enhance firms' managers participation in research
