Complementary and Alternative Medicine (CAM) is a heterogeneous group of theories and practices that are becoming increasingly popular in the West – between 20% and 65% of patients use CAM on a regular basis. In the UK, CAM is provided by over a third of general practitioners as well as by hospitals. The subject of much debate in both the lay and medical press, CAM is subject to increasing scrutiny from clinical research. In this review, we discuss the available evidence for herbal medicines, including that for silymarin, glycyrrhizin, Chinese herbal medicines and other herbal mixtures. We also review evidence regarding the safety of herbal medicines, both in terms of hepatotoxicity and drug interactions. We conclude that although CAM may be of benefit in the treatment of liver disease, the available evidence is insufficient to recommend any of the available therapies. CAM has not yet been well studied in liver disease and rigorous evaluation with well-designed double-blind randomised controlled trails is required. Doctors need to be aware of the widespread use of CAM, ask their patients specifically regarding their use of CAM and be aware of the potential for hepatotoxicity and interactions.