If your organisation sells memberships or subscriptions to Businesses, there are now 3 great ways to allow that organisation to add members AND you can optionally give these new members instant subscription access without manual intervention (although you can do this easily manually too).

 
Method 1
If you make the relationship between the main account holder and the supplier/organisation an 'isOwner' relationship type, they get the option to edit their own organisations basic details (logo, name, abn, phone, website) but can also add and remove users from the organisation. When they add a member,  it is added to your main member database and linked to this organisation.

Pro tip: Add a workflow to automatically assign a subscription to certain members as they are added.

Method 2
You can use the domain in a suppliers account, to add the email domain extension, for example fo mition, we use the email extension mition.com. Add that to each supplier. Then add a workflow that automatically registers users based on their email extension.

Method 3
Use the Registration (Corporate) web component, this gives staff the ability to tailor a subscription type that will be given, then create a link for each supplier (you need to preview the page as a staff member to create a link). Each link is directly related to a specific supplier and users will be added to that supplier as well as given any subscription required.