The quality and reputation of an academic journal can depend on several factors, but high-quality peer reviews are always a core requirement. Unfortunately, reviews are not always up to the standard that they should be. Poor reviews can result in a number of problems including sub-standard articles being accepted and good manuscripts being rejected. Good reviews are comparable to good papers; they require attention and dedication to write well. Although journals are different, it is important that reviewers approach their task with goodwill, i.e. that they approach a manuscript with an open mind, read it with care and attention and make comments that are constructive and show self-reflection. Reviewers need to know the evaluation standards and the limits of their own expertise and, if in doubt, not to be afraid to say so.