Linking two cells

Hello! Say I have got two excel-tabs: One containing persons (customers) and their phone number, in two different columns. This tab is called "customers". Another tab is called "orders". In the tab "orders", I've created a scroll list, where you can click and choose a person in the "customers"-tab. Now my problem is this: Is it possible to make the customers phone number appear in the cell next to the cell with the list function automatically in the "orders" tab??