This paper introduces a special issue of the journal devoted to work presented at two recent conferences of the Association for Heterodox Economics (AHE). The AHE is an organisation which advocates and provides a forum for non-mainstream approaches to economics. Recent conferences have focused on pluralism. Pluralism is a variegated concept with multiple motivations and arguments in its favour. Such arguments tend to be ontological and epistemological, but may also be pedagogical. Pluralism has been advocated as a moniker preferable to heterodoxy which might be adopted by non-mainstream economists. However, it is problematic. The papers which comprise the remainder of this issue illustrate that point. The papers are discussed in turn and contrasted.