Mathematical models of cardiac cellular electrophysiology have evolved significantly over the last 50 years. Beginning with the initial four ODE models from Noble in 1962, models are now being developed with many tens of differential equations requiring hundreds of parameters and integrating multiple aspects of cellular physiology. Such increases in complexity inevitably result in significant barriers to the use of the models by independent scientists or even application of existing models in novel scenarios. Technologies are being developed which negate these barriers to some extent and provide tools to aid model developers and users in the reuse of previous models. In this chapter, we review some of the common cardiac cellular electrophysiology models and place them in the context of current model description technologies in order to illustrate the current state of the field.