In this article, we draw upon the philosophy of critical realism to reflect upon issues concerning discovery processes and opportunity development. First, paradoxes in the relationship between opportunity discovery and creativity are identified and explained. Second, the question of how to investigate opportunities is discussed and a solution informed by critical realism presented whereby three new types of discovery are identified and defined for empirical investigation. Using critical realism to augment entrepreneurial opportunity theory, we propose that discovery processes have significance (...) beyond discovery theory and can be considered revealing for theories of opportunity development more generally. We conclude with conceptual and practical comment on the importance of ontological theorising for entrepreneurship. (shrink)