<p class="AbstractTxt">This paper aims to provide a summary of some of the key issues outlined in my recent publication <em>Realist Criminology</em> (2014a). It discusses, in particular, the perceived deficiencies of both mainstream and critical criminology in relation to their explanations of the crime drop. It argues that the failure of criminologists to provide a convincing and plausible explanation of the recent decrease in recorded crime in Britain, North America and other countries has resulted in a new aetiological crisis. It is suggested that the failure to explain what is arguably the most significant development in relation to crime in living memory is no accident, but rather a function of the theoretical and methodological inadeq...