The purpose of this special issue is to critically examine the constructivist moorings of contemporary developmental theory and practice, including the practice of research methods. This introduction to the special issue is intended to foreshadow the papers presented here by charting the terrain of several conceptual commitments that we consider paradigmatic cornerstones to constructivist approaches. Although constructivism has deep roots across disciplines in the sciences and humanities, generating a wealth of scholarship focused on its various assumptions and theoretical principles, here we target three: the active subject, normativity, and historicity. These principles are theoretically axiomatic of constructivist approaches, strongly interconnected, and highly relevant to some of the most pressing debates and challenges affecting contemporary science and society, not the least because they question fundamental notions that we often take for granted – notions as vital as the meanings of truth, fact, and objectivity. After presenting a primer on the meaning and significance of these three principles, we review their status as critical signposts for the work of scholars contributing to this special issue.