Peer review is at the core of scholarly publishing; it is the lynchpin around which the whole research information exchange is based. Recently, the process has attracted criticism. In this global study, which was conducted in the later part of 2009, we examine the influences and attitudes of over 4,000 researchers towards peer review. We find that peer review is valued, but needs to be improved. Most reviewers are actually keen to review, but believe formal training of reviewers would improve peer review. Publishers and editors need to become better at matching reviewer expertise to manuscript subject. The research community believes overwhelmingly that double-blind peer review is the most effective form of review, and that formal peer review would benefit from some form of post-peer review commentary.