WorkfloPlus allows you to control which users and groups can access individual workflows.
Permissions can be set for each individual workflow in the Workflow Details Panel. To set permissions, select the workflow for which you would like to set permissions to open the Workflow Details Panel. Under permissions, if there are no users or groups specified then the workflow will be available to all users.
To restrict access to specific users and groups enter the users and groups that require access (all unspecified users and groups will lose access).