There are several permissions relating to workflows within Document Management. These are set in the Task Permissions window which can be accessed via File > Maintenance > Security > Task Permissions.
In the Product dropdown select Document Management, and then select the appropriate security group in the Group dropdown.
There are permissions available under the the following Group Descriptions:
#Document Centre #Start Workflow
This permission allows users to start a workflow against a document from within the Document Centre.
#Document #Workflow AllowNone
This permission will allow users to opt not to use a workflow (where there are associated workflows) when adding or creating documents.
#Document #Workflow OverrideDefault
This permission will allow users to select a different workflow to use (where a default has been set).
If neither of these permissions are granted to a user they will not be able to change any default workflows that are set.
[Maintenance][Document Management][Document Workflow]
This permission allows users to access and make changes in Maintenance > Document Managment > Workflows.