Microsoft Dynamics 365 Business Central 
 My Top 10 Favorite Things
#3- Single Sign-On Logins & the Association with Office 365

Of all my favorite things in the world, remembering passwords and authentication questions is not one of them.
Do you ever get sick of logging in and out of programs all day long?
Microsoft understands this problem, which is why Dynamics 365 Business Central works with your Office 365 credentials and a single sign-on authentication.

What Does This Mean? 
When I log into BC and I remember my credentials, it authenticates me against my computer account which is associated with my Office 365 account.

Does This Mean I Must Have Office 365 to Run Dynamics Business Central? 
Yes, you must have
 Office 365 licenses to run Business Central.

Why the Association? 
Associating your Office 365 logins with Business Central allows for quicker login access, one single password for all Microsoft products, and easy security admin for your IT users. Your IT users grant access to Business Central through your Office 365 admin portal, the same way they would your Office 365 license is assigned.

This association allows you to access and utilize the same credentials to work with the Business Central adapters for Excel, Word, SSRS, Azure and Power BI. Thus allowing users to not have to login and logout of all these programs.

How Do I Grant Security Rights to BC Users? 
Once a user has access through the O365 Admin Portal, a security admin within the Business Central Site can grant user security rights. There is no need to key in the users inside Business Central, you can simply run the update users from Office 365 tool to see all users who have access in the portal.

Going forward, this one universal Microsoft single sign-on leans the Microsoft expansion of Office 365 and Dynamics 365 offerings towards a "One Microsoft World".