Abstract: The B Corp certification has emerged as a means to measure the social, environmental and economic impact of companies. The number of certified companies has been growing steadily for the last years, with almost 4000 B Corps at present. Despite this fact, this is an incipient field of research and there are very few studies focused on the B Corp certification process itself. In fact, there are no studies focused on the barriers companies found when pursuing the certification. Thus, in order to cover this gap, it seems necessary to develop new studies based on companies? own experiences. As there is not a commonly accepted and validated measurement tool (questionnaire) to gather primary data, the objective of this article is to design and propose a questionnaire that collects the motivations, barriers and effects companies experienced during the certification process through a Delphi study. Nine stages are followed from the definition of the research questions and the literature review, to the creation of a final questionnaire. In this study, the panel of experts was integrated by 20 experts and two rounds were conducted. The final questionnaire, named B Corp Certification Process Survey (BCCPS), is made up of 10 motivations, 12 barriers, and 20 effects. Having a common questionnaire allows comparisons and fosters the development of the research field.