A correspondent who is usually well informed about time zone matters sent me a correction to my time zone data for Western Sahara. He says that Western Sahara observes daylight saving time, just as Morocco does. The tz database shows it as Africa/El_Aaiun with no DST. The status of Western Sahara is disputed, but Morocco has de facto control over some 80% of the territory, including El Aaiun (a.k.a. Laâyoune). It seems logical that the clocks would be set to the same time as Morocco. For what it's worth, the CIA World Factbook says that in Western Sahara, DST "begins last Sunday in April; ends last Sunday in September." If it can be confirmed that El Aaiun's time is the same as Morocco's, the Zone info for Africa/El_Aaiun should be changed to match Africa/Casablanca, at least after 1991-09-06 (the date of the cease-fire that ended the Western Sahara War), and possibly as far back as 1976-02-20 (the date when Spain abandoned its possessions there). Gwillim Law