Purpose -Although there are often utilized the case research method for teaching purposes, it is not a method employed to move forward in scientific research into business ethics, perhaps due to criticism levelled against it. The precise aim of this work is to expound and argue for its use within the framework of scientific hypotheticaldeductive methodology. Design/methodology/approach -The opportunities offered by this methodological approach, both from an inductive (Eisenhardt, 1989;Dyer and Wilkins, 1991) and a deductive perspective (Yin, 1993;Carson et al., 2000) have been wasted, creating a need for scientific contributions within this area; hence this study. It was carried on a theoretical approach of the use of single case applied to corporate management based on religion and spirituality inclusion. Findings -The results obtained indicate that the single case research method makes it possible to put forward alternative hypotheses to the dominant hypothesis, making contributions to the theory. Concretely, the scientific legitimacy of its use is justified by what it has been called "possibilistic hypothesis" for what it is not necessary to collect a large data or make an empiric research. Practical implications -In the field of business ethics these hypotheses (possibilistics) make alternatives stand out that widen the moral responsibility of decision-makers. It implies an open mind for decision-makers and rigorous arguments using just a single case. Reinforce and make them easier based on moral imagination improvement. Originality/value -It is complex the decision process, but this rich method, the singlecase study could permit establishing rigorous and robust decisions easily. It is not use the case study widely for management, but this perspective could enrich and increase its use.