Microsoft has recently announced Teams Guest Access opening up the door for “federation like” communication between Office 365 Tenants that are using Teams. The process for adding Guests is documented here however there are a few caveats you need to be aware of.
1. The Guest you are inviting needs to have Teams enabled. This seems kind of obvious but if they don’t have access to Teams they won’t be able to sign on to take advantage of the invitation they just received to join another Team. In Office 365 ensure the user has the appropriate license assigned and ensure that Teams is enabled for them individually. Some Tenant Admins also turn Teams off at the Tenant layer so also ensure this is not the issue first.
Of course, both above settings relate to the Tenant of the Guest you are inviting so you will need to reach out their IT Administrator to ensure the about requirements are true. At the time of publishing this it does not appear Teams is doing a check to see if the target user meets all the current prerequisites of accepting and joining as a Teams Guest. This would be an ideal feature enhancement.
2. Your Organization needs to allow you to invite Guests. Check with your IT Administrator to make sure you are allowed to invite Guests to your Teams. Currently this is a Tenant Level Setting meaning it is either On or Off for all Teams Users within your organization. In Office 365 go to the Settings, Services & Add-ins, Office 365 Groups option. I’m not a fan of how this is laid out but essentially the second option controls whether you can invite Guests to your organizations Teams and the first option controls the access that guests that already have been invited have. Notice that these features are controlled within the Office 365 “Groups” settings given the tight integration of Teams to Groups.
Figure 3: Allowing your Organization to Invite Teams' Guests
With time I expect that the user experience around the Teams ‘federation’ model improves. Once of the other caveats is that the user joining as a guest must sign out of their Teams Tenant and into the “Guest” tenant of the organization that has invited them. While in this tenant it means they miss conversations and meetings that are happening in their own tenant. I’m hoping and again expect that the experience here also improves.