Patient adherence to medication continues to be a cause of concern within the medical profession. This review examines the various methods of quantifying the level of patient adherence, progress in predicting causes of non-adherence, and the implications for its management. Contributions from the medical, health belief, and psychosocial models are discussed in order to highlight how the concept of adherence has changed over time. The impact of epilepsy, seizures, and taking antiepileptic drugs (AEDs) on both adherence and quality of life are also explored. The volume and quality of previous research conducted has enabled a number of predictive factors to be identified, from which various strategies have been developed. While this review concentrates on potential strategies in managing treatment adherence within epilepsy, findings can equally be applied to other chronic conditions.