The increasing influence of socio-organizational issues in information systems poses serious challenges to the applicability of most traditional research approaches, since the mechanisms from which they derive their rigor and validity become more and more unrealistic in the new contexts. Indeed, traditional problem decomposition, standardization of procedures, and rigorous quantitative measurement under the control of independent researchers often lose sense in such contexts. We analyze action-research as an alternative approach, bearing in mind that its adoption requires careful consideration of the epistemological foundations that legitimate its use. In particular, we address the legitimacy of generalizing from the researcher’s findings, bearing in mind Karl Popper’s critical rationalism, to conclude that a virtuous relationship exists between critical rationalism and the mechanisms from which action-research draws its rigor and validity.