The Board of Editors in the Life Sciences (BELS) was founded in 1991 to evaluate the proficiency of manuscript editors in the life sciences and to award credentials similar to those obtainable in other professions. Potential employers and clients of manuscript editors usually have no objective way to assess the proficiency of editors. For their part, editors are frustrated by the difficulty of demonstrating their ability. That is why both employers and editors so often resort to personal references or ad hoc tests, not always with satisfactory results. The need for an objective test of editorial skill has long been recognized. To meet that need, the Board of Editors in the Life Sciences (BELS) developed a process for testing and evaluating proficiency in editing in the life sciences. The Board administers two examinations–one for certification and one for diplomate status. The examinations, written by senior life-science editors assisted by testing experts, focus on the principles and practices of scientific editing in English. Mission: To maintain and promote a standard of proficiency in editing in the life sciences. Vision: To improve communication in the life sciences through certification that supports the role and value of editorial professionals.