Systematic reviews and meta‐analyses are one of the cornerstones of evidence‐based medicine. The conduct of this type of research allows the precise estimate of the effects of health care, and is sometimes of sufficient importance to alter clinical practice. However, like any type of research, systematic reviews and meta‐analyses are subject to bias, which often arises from the published literature available to the researchers, and may have other potential methodological limitations. This chapter discusses these potential biases and limitations in detail, as well as providing the reader with sufficient information to critically appraise systematic reviews and meta‐analyses in detail, in order to decide whether or not the findings should be incorporated in to their clinical practice.