The Z User Group (ZUG) was established in 1992 to promote use and development of the Z notation, a formal specification language for the description of and reasoning about computer-based systems. It was formally constituted on 14 December 1992 during the ZUM'92 Z User Meeting in London, England. Meetings and conferences ZUG has organised a series of Z User Meetings approximately every 18 months initially. From 2000, these became the ZB Conference (jointly with the B-Method, co-organized with APCB), and from 2008 the ABZ Conference (with Abstract State Machines as well). In 2010, the ABZ Conference also includes Alloy, a Z-like specification language with associated tool support. The Z User Group participated at the FM'99 World Congress on Formal Methods in Toulouse, France, in 1999. The group and the associated Z notation have been studied as a Community of Practice. List of proceedings The following proceedings were produced by the Z User Group: Bowen, J.P.; Nicholls, J.E., eds. (1993). Z User Workshop, London 1992, Proceedings of the Seventh Annual Z User Meeting, 14–15 December 1992. Springer, Workshops in Computing. Bowen, J.P.; Hall, J.A., eds. (1994). Z User Workshop, Cambridge 1994, Proceedings of the Eighth Annual Z User Meeting, 29–30 June 1994. Springer, Workshops in Computing. Bowen, J.P.; Hinchey, M.G, eds. (1995). ZUM '95: The Z Formal Specification Notation, 9th International Conference of Z Users, Limerick, Ireland, September 7–9, 1995. Springer, Lecture Notes in Computer Science, Volume 967. Bowen, J.P.; Hinchey, M.G.; Till, D., eds. (1997). ZUM '97: The Z Formal Specification Notation, 10th International Conference of Z Users, Reading, UK, April 3–4, 1997. Springer, Lecture Notes in Computer Science, Volume 1212. Bowen, J.P.; Fett, A.; Hinchey, M.G., eds. (1998). ZUM '98: The Z Formal Specification Notation, 11th International Conference of Z Users, Berlin, Germany, September 24–26, 1998. Springer, Lecture Notes in Computer Science, Volume 1493. The following ZB conference proceedings were jointly produced with the Association de Pilotage des Conférences B (APCB), covering the Z notation and the related B-Method: Bowen, J.P.; Dunne, S.; Galloway, A.; King. S., eds. (2000). ZB 2000: Formal Specification and Development in Z and B, First International Conference of B and Z Users, York, UK, August 29 – September 2, 2000. Springer, Lecture Notes in Computer Science, Volume 1878. Bert, D.; Bowen, J.P.; Henson, M.C.; Robinson, K., eds. (2002). ZB 2002: Formal Specification and Development in Z and B: 2nd International Conference of B and