I would like to stress that this Feature Request is really crucial to Knack users like me who are selling to a multitude of multi-person entities. There are three scenarios for the use of Knack.
A Knack account is used to create an app that is:
 used by a multitude of single-person customers,
 used by a multitude of users within a single entity,
 used by a multitude of multi-person entities.
Scenarios  and  are fundamentally similar. Scenario  is very different.
My distinction between [1 & 2] and  is that the customer for a Knack-built app in [1 & 2] is a single entity (whether John Doe or the Marketing Department of Proctor and Gamble) and in  the customer for the Knack-built app is a multitude of multi-person entities (businesses like real estate offices, architectural firms, or franchises).
The absence of a way to completely isolate one multi-person entity from another in my app is a constant limitation. This affects filtering the most (at the moment). Only objects and fields that are common to all multi-person entities can be filtered without exposing the custom data of other multi-person entities. This means that you can only filter by Date and by fields that are either/or. Every other type of field's data is exposed to every multi-person entity when filtering, in other words every record of every multi-person entity appears in the filter choices.
I had suggested that you need another level in the User Roles Objects area: *Organizations* > Accounts > User Roles. Another way of looking at it would be Accounts > Sub-Accounts > User Roles so that Sub-Accounts of an Account could share records.