Hi there Jammie, yes that is more than possible. In fact I would suggest using it if you have it. Simply cable the 2 together, set up the Airport Express and then turn off the broadcasting on the Business hub. Does the Airport Express run it's own DHCP? If so you may need to disable that. To stop the broadcasting on the business hub visit http://192.168.1.254 then click on wireless. Simply untick the broadcast checkbox. Scroll to the bottom and click save. Hope this helps.