This volume contains the papers presented. at the Third IFIP International Working Conference on Dependable Computing for Critical Applications, sponsored by IFIP Working Group 10.4 and held in Mondello (Sicily), Italy on September 14-16, 1992. System developers increasingly apply computers where they can affect the safety and security of people and equipment. The Third IFIP International Working Conference on Dependable Computing for Critical Applications, like its predecessors, addressed various aspects of computer system dependability, a broad term defined as the degree of trust that may justifiably be placed in a system's reliability, availability, safety, security, and performance. Because the scope of the conference was so broad, we hope the presentations and discussions will contribute to the integration of these concepts so that future computer-based systems will indeed be more dependable. The Program Committee selected 18 papers for presentation from a total of 7 4 submissions at a May meeting in Newcastle upon Tyne, UK. The resulting program represented a broad spectrum of interests, with papers from universities, corporations, and government agencies in eight countries. Much diligent work by the Program Committee and the quality of reviews from more than a hundred external referees from around the world, for which we are most grateful, significantly eased the production of this technical program.