In this contribution, we discuss three recent developments in atomistic biological charge transfer theory. First, in the context of Marcus' classical theory of charge transfer, key quantities of the theory such as driving forces and reorganization enthalpies are now accessible by thermodynamic integration schemes within standard molecular dynamics simulations at high accuracy. Second, direct simulations of charge transfer enable the computation of fast charge transfer reaction rates without having to resort to Marcus' theory. Finally, exploring the electronic structure beyond that of hitherto presumed centers of localization helps to identify new stepping stones of charge transfer reactions. This article is part of a Special Issue entitled: 17th European Bioenergetics Conference (EBEC 2012).