If memory serves me correctly they had a distinct mission during the Cold War for a WW3 scenario, but I'm not sure how that has evolved since then. The only real information I'd heard about them since then (but not being British, I don't pretend to be really in the loop) made it sound like the supplement the full time guys. As for reserve versus full-time operators, here in comparable US units the situation is quite a bit like the broader reserve/active-duty situation. You have some guys who are over the hill or whatever, but at the company level and below proficiency is usually close to comparable (or can become comparable during a mobilization train up -- particularly in reserve SOF and otherwise special units that usually strive to maintain standards more effectively the reserve units with lower esprit de corps and such). The recurring bigger problem is getting battalion and higher staffs proficient and up to speed.

I think 23 SAS are the reserves and 21 SAS are the Territorial Army's SAS. There is a difference bettween the two. It could be the other way round, I can't quite remember.

i thought they were both Ta just that they recruited from different areas 21(artists rifles) from london and the south and 23 from the north - i could be wrong though

Other than the Australian SAS, are there other SAS units i.e. New Zealand, South Africa or elsewhere?

I knew a bloke in 21 SAS although he didn't talk much about it and I didn't ask. I know he was in the balkans quite a few times though.

the new zealanders have an sas unit of their own. the canadian equivalent are called JTF and a number.

Yeah, the Canadians call their SOF capability "Joint Task Force Two" (begging the question of who is JTF One . . .). Outside of the UK, Australia, and New Zealand, I'm not familiar with anyone else currently using the SAS term. Rhodesia notably did in the past, as well as some of the Free European forces in WW2.

There are 3 international SAS units Aussie, Brit and Kiwi. Four if you include the French PATSAS (There were originally some French SAS units, hence the lineage. In answer to your question there are actually 4 SF TA units. 21 SAS Southern UK, 23 SAS Northern UK, HAC city (Long Range Surveillance and Target Acquisition squadrons) and the RMR SBS. The main role of the TA SAS is to conduct CTR(close target recon) for the Intelligence corp. This is a throwback to when the role was defined by cold war planning. 22 are also loathed to give up too many of their regular skills (CRW,CP etc , etc) So the role of the TA units up until recently has been limited by the directorate of Special forces. The training for the TA SAS is a shortened version of the regular SAS selection. Many regs complain that the STABS get too much of a break in between tasks and are therefore at a distinct advantage to regular selection candidates ( TA SAS selection is conducted every other weekend) There is a week long battle camp at the end of selection, where the recruit is put through an E&E exercise and then questioned using TQ- tactical questioning) Succesful candidates then move onto continuation training. Troopers who have the time can apply to do the regular version of courses after selection. It must be pointed out that although the roles of the two units differ somewhat, there is an increasing interoperability between 22 and it's TA counterparts. This is due in most part to the increasing shortages in manpower, 21 & 23 troopers conveniantly fill the gaps in the regular sqaudrons. Because many of the TA troopers are gaining more active experience and obtaining many of the advanced SF skills normally limited to 22 SAS. The operational capabilities of the TA units is slowly changing. 22 are too busy to resist this change and so 21 and 23 troopers are increasingly being used for the jobs that were the sole task designation of 22 SAS. Sorry my answer has been so long winded but in summary the TA SAS has mainly a recon role but that is changing due to the manpower pressures put on the UKSF by the War on terror.

Thanks for the update. The Danish Home Guard did a lot of training with them and the USRangers - still do as far as I know.