Preliminary work on the development of measures appropriate for the safety domain is reported. Measures are expressed in the style of the Practical Software and Systems Measurement (PSM) approach, a programme sponsored by the US DoD. Proposed measures are integrated with the PSM measurement framework. Reported work has been informed by discussions within the PSM community and by concurrent work on the safety extensions to CMMISM , derived from the +SAFE safety extensions project, sponsored by the Australian Department of Defence. The paper discusses the background to the work, locates it within a measurement framework for the safety domain and proposes a set of measures, with justifications. The paper closes with an assessment of progress in safety measurement and identifies areas needing further work.