Background: The radiation treatment community has traditionally had a strong focus on the safety and quality of the care provided to cancer patients. Recent well publicized events in the United States and around the world have served to further sharpen this focus and have resulted in the generation of many reports offering advice and recommendations on how we could do better. While advice is plentiful, practical tools for the on-going improvement of safety and quality in radiotherapy are generally lacking. The online Safety Profile Self-Assessment Tool, described here, is being developed to fill this gap. Methods: The tool was built principally on three foundations: The Agency for Healthcare Research and Quality’s (AHRQ) validated survey tools, an analysis of recommendations in seven recent authoritative documents and the AAPM’s Work Group on the Prevention of Errors “Consensus recommendations for incident learning database structures in radiation oncology”. A core group developed a demonstration version of the tool. Both the content and functionality of this version were extensively discussed and further developed at a Workshop including representatives of ASRT, ASTRO, AAMD and SROA. Iterative refinement of the tool took place after the Workshop. Results: The tool is divided into four major sections: (1) Institutional Culture, (2) Quality Management, (3) Managing Change and Innovation, and (4) Clinical Performance. The fourth section, Clinical Performance, is further subdivided into the major steps in the radiotherapy process. The 90 safety/quality indicators take the form of statements with which the assessor identifies the degree of compliance on a five point Likert scale. An example of a Safety/Quality indicator isClinical staff submits reports of errors and near-misses.The assessor responds to this statement on a scale ranging from “Always” to “Never”. The online tool includes a Safety/Quality Improvement log to facilitate tracking the implementation of remedial actions taken in response to identified system weaknesses. Conclusions: An online tool to facilitate Safety/Quality improvement in Radiotherapy is at an advanced stage of development. The tool will be released for general use in the fall of 2012 and fully evaluated thereafter.