The ability to receive shipments from multiple carriers and have them consolidated in one system for shipment tracking. It's very easy to use once you understand it. I wish there was more integration options between Shipfusion and 3rd party vendors/apps such as email marketing software. We ship out over 100,000 shipments per month and ShipFusion has been able to help us streamline our shipping process. I really like that I can have multiple email addresses linked to different ShipFusion accounts. It's a bit more complicated than just having one email address but it's an easy way to have multiple email addresses. We are solving the problem of people ordering products online and not being able to receive updates on their orders. It also saves shipping costs since we are able to ship from our own warehouse rather than using a shipping company.