Threading like Gmail is called "Show as Conversations" in Outlook. It's been available since 2010. They work almost identically as far as I've noticed (I use bo

Threading like Gmail is called "Show as Conversations" in Outlook. It's been available since 2010. They work almost identically as far as I've noticed (I use both Outlook and the web interface to my Google Apps email account most days). I'm not sure when exactly it was added, but this dropdown near the search input controls the scope: https://www.dropbox.com/s/7x35rgahnuultnp/outlook-search-all-items.png?dl=0 https://www.dropbox.com/s/7x35rgahnuultnp/outlook-search-all... For a while before, you could still search globally. If you did a single folder search, there was a link/button/something to expand the search to all folders if you didn't find what you were after in the single folder. The key with Outlook search is that you need to let the indexing service run. Search from within Outlook depends on that index for quick searches.