This chapter outlines the importance of critically reflecting on the diagnos- tic criteria for DMDD now included in DSM-5. In so doing, it mounts the argument that DMDD is a new and problematic inclusion to the 'Depressive Disorders' in an extremely influential manual of psychiatric disorders. Sig- nificantly, the inclusion of this new 'disruptive' and 'energetic' disorder as a form of 'depression' has yet to meet with substantive critique. DMDD crite- ria include 'tantrums', a point that has been hotly debated. For instance, as Wakefield (2013) pointed out, 'Children tend to outgrow these temper tantrum problems, so treatment and stigma may be applied unnecessarily to large num- bers of children' (2013, p. 150). It is unknown how this new child disorder will impact, positively or negatively or even if it will afford the clarity that it is hoped to deliver. As Gitlin and Miklowitz (2014) concluded, 'whether this new category will advance diagnostic clarity and/or more appropriate treat- ment is unknown' (2014, p. 89). The chapter demonstrates how historically informed analysis can be drawn upon to reflect on how interpretations and representations of melancholia and depression are very much connected to the political, the discursive, and, in the 21st century, to the authors of one manual of mental disorders. For a simple summary of the implications for practice, see Table 10.1.