During the past decade, long-range radical cation migration in DNA has been an area of extensive experimental and theoretical examination. The motivations for the vigorous investigation of this topic are its potential to yield a deeper understanding of the processes that cause oxidative damage of genomic DNA and the potential for use of DNA architectures in molecular electronics. This investigation has revealed the mechanisms of charge transport and the limitations of DNA as a functional element in devices. In this article we discuss various aspects of the radical cation migration process and present the plausible mechanism by which this process occurs.