This document summarizes TRAFFIC's comprehensive overview of events and dynamics currently driving an escalating illicit trade in rhino horns from South Africa to Viet Nam. Whilst it is recognized that there are other dimensions to the rhino horn trade within Africa and in Asia, this examination of the two principal countries serves to bring into focus many prominent characteristics of a still unfolding wildlife trade crisis of global importance. The story for South Africa is a data-rich narrative that underscores the intense preoccupation and commitment of that nation regarding rhino conservation. In contrast, almost no empirical data exist for understanding the Vietnamese side of the equation, which comes into focus primarily through a growing body of observational and anecdotal accounts. Regardless of any shortcomings, it is hoped that this effort will make a valuable contribution towards understanding the salient factors both in source country and end-use market that underlie the current rhino crisis. In turn, this knowledge should lead to remedial strategies, actions and interventions that serve to mitigate and prevent further losses of Africa's iconic but threatened rhino species.