Declining public trust in journalism and an ever-expanding roster of new platforms and providers of news have spurred calls for greater transparency as a way to re-assert traditional journalism’s place in the news landscape. Transparency is understood as an important method for holding journalists accountable, thereby promoting credibility and trust. For all the attention transparency has received in the profession and among researchers, definitions of it are lacking, complicating efforts to assess its impact. This chapter offers a synthesis of the literature, revealing two primary understandings of the term—availability and disclosure—and suggests areas where further conceptualization and research are needed.