Burke presents a much-needed, non-purist perspective on why organizational safety research and safety training evaluations need to be proportionate. Being proportionate concerns safety professionals choosing the most rigorous study plan, given constraints, to determine if a safety intervention made a difference. Beginning with measuring safety criteria, he discusses the choices that can be made concerning the types of measures and sources of information when assessing workers’ reactions, knowledge and skills, safety motivation, safety performance, and safety outcomes. Importantly, he skillfully discusses the strengths and challenges of using each criterion measure in safety investigations and practice. Further, he provides clear examples of the use of each criterion measure along with in-depth, practical advice on the development and use of safety performance measures.