In Interspire Email Marketer you can create multiple user accounts. Within these accounts you can set different permission levels, grant access to different templates, contact lists etc.
This can be useful if you wish to create accounts so that your employees can have access to their respective departments such as an account that can only design your templates and email layout etc and another account that can then manage the contact lists and send emails to those contact lists.
You can also resell Interspire Email Marketer to other clients, allowing them to login to your application as another user so that they can send out their own personal contact lists.
