"Metacognitive theories," an article Gregg Schraw and I published in "Educational Psychology Review" in 1995, has been cited in over a thousand scholarly publications. In this follow-up, dedicated to Gregg and written after his recent death, I provide a brief overview of our 1995 article and then reflect on it in four ways. First, I consider the development of the concept of metacognition prior to 1995, including its emergence and use in previous writings by each co-author. Then, I turn to the collaboration itself, including the interplay of complementary conceptions and the construction of new ideas. Third, I consider the article's citation history and the role it has played in the subsequent literature. Finally, I discuss research on metacognition since 1995, including subsequent work on epistemic cognition by each of the co-authors.