I am a software engineer working for an avionics company. I am currently working on a project that requires the software I will create to know the time *any place on earth given a latitude and longitude*. Time zone boundaries and time rules will need be *updated on a monthly basis*. This task is proving to be very difficult. The most difficult part is getting up to date data on for time zone boundaries. *Most of the services and databases I have researched only give time zone information for a particular city in that given time zone (ie. Olson Time Zone Database), I have yet to find anything that defines the actual time zone boundaries.* *Is there a service or database that gives up to date boundary and time rules monthly, and has worldwide coverage?* Thanks in advance, Rod Williams