Contact Groups give you control of RFQ notifications, allowing you to notify only specific Contacts from your Suppliers. 

To start setting up your Contact Groups, an admin can navigate to System Settings, and then select Contact Groups on the left of the page to start:

You can click '+Add New Contact Group' to create a grouping. 

Once you've added your grouping, navigate to the Suppliers module, and select or create a new suppliers to start assigning your contact groups.

When creating a new Contact, you'll see a drop-down on the right to allow you to select your existing Contact Groups:

Or click the pencil icon on an existing contact for a supplier to edit and assign a contact similar to above:

Once the Contact Group has been assigned, when creating a new RFQ, you'll see a drop-down allowing you to select Contact Groups:

 

When your RFQ is created, and assigned, only the assigned supplier contacts with matching Contact Groups (or Contact Group set) from the chosen Suppliers will be notified of the new RFQ assignment. 

Please note, that Contact Groups only affects the groups that are notified of the new RFQ creation and does not affect access to RFQs in any way.