You don't buy it separately, but if you have Office 365 already, it's "free". If you're already paying them money, it's just there and is somewhat integrated w

You don't buy it separately, but if you have Office 365 already, it's "free". If you're already paying them money, it's just there and is somewhat integrated with the rest of the apps, but I doubt there's a lot of orgs out there purchasing Office 365 specifically because of Teams.