This volume contains the proceedings of the third International Workshop on Computer Aided Verification, CAV '91, held in Aalborg, Denmark, July 1-4 1991. Thee objective of this series of workshops is to bring together researchers and practitioners interested in the development and use of methods, tools and theories for automatic verification of (finite) state systems. The workshop provides a unique opportunity for comparing the numerous verification methods and associated verification tools, and the extent to which they may be utilized in application design. The emphasis is not only on new...