The proliferation of operationalisation approaches to safety climate has failed short of establishing a common set of dimensions and measurement items. Furthermore, extant measures are designed to accommodate all organisations regardless of safety management maturity; thus, a safety climate measurement scale suited to high-maturity organisations is still missing. Drawing on a systematic review of safety climate measurement literature, the article reports the development and validation of a multi-dimensional and multi-level safety climate measurement scale, suited to organisations with high safety management maturity. To corroborate the validity of the measure, the study was conducted in cooperation with health & safety managers from 15 large companies with a mature safety management system. Following initial questionnaire development, a multi-stage validation procedure was implemented on data from four large companies (totalling 880 participants) operating in the electric power distribution, oilfield services, manufacturing, minting and printing sectors in Italy. Exploratory factor analysis was used for the identification of the underlying structure of the set of items. Confirmatory factor analysis was undertaken to evaluate the model fit at the validation stages. The final version of the questionnaire consists of eight safety climate dimensions and 60 items. A short version of the scale is also validated to provide a more balanced, while complete and reliable, measurement tool (totalling 40 items). Lastly, implications for safety practitioners are discussed, providing directions on how to utilise the scale for identifying safety improvement opportunities.