International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / This paper will present a selected overview of calendars and calendar development from antiquity to the current Gregorian calendar. The current hot topics of the GPS 1999 Rollover and the Year 2000 Millennium Rollover will be explained.

International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / This paper discusses the successful passage past the Year 2000 (Y2K) Rollover and GPS 1999 (Week Number Roll Over) WNRO. The reasons the glitches seen at those events were relatively minor and the lessons learned to help enter the Third Millennium with careful optimism are reviewed.