OK. Here's the set up. Personal - all on Mac Work - in outlook 2010 on windows 7 (on fusion) Mail - more or less works but haven't found out how to get aliases to work without creating lots of the same inbox in outlook (even when using scheduler). So just go with work email alias in Outlook. Not too much of a problem. Calendar - what a mess If handle meeting request in Outlook (which is great in this respect) and I create appointment there then it goes to the Outlook default calendar. This doesn't sync with MM so no reminders or visibility in mac environment or more importantly on iphone. If I change default calendar in Outlook, I lose ability to manage tasks etc in Outlook. One solution is to share outlook calendar and receive as a shared calendar in Mac (but does not sync to iphone) If I accept under Mac Mail then more or less OK with @me.com mail but does not sync to Outlook. If has been sent to a pop3 account, then can not use MM calendars so does not sync to iphone - not acceptable. Finally can not control which calendars are synced (at either end) or what gets written where when syncing so lose data and get stuff I don't want. Contacts - given up Contacts seem to be held in different formats. Information like emails does not get across properly and by the time the second sync happens the emails get deleted from Mac contacts as well. Deleted contacts reappear, current contacts get updated without out of date information ... Just need to do changes in both systems - a pain but more or less OK as don't change that often. then to add insult to injury, the mobileme sync in windows is running at 100% of cpu so I've had to disable that as well. By the way - I don't have exchange server. This is definitely not something that "just works". Thoughts?