The ability to create custom fields, as well as being able to assign them to contacts. You can also have multiple tabs for different types of data entry. There are many things you can customize in this software that would be difficult with other systems out there. It's not easy to use and it doesn't seem like they're making any changes toward improving their user interface or customer support. We've been using it for several years now but we still struggle with some tasks because of how complex the system really is. We haven't realized all the benefits yet so I'm sure once we do everything will become easier! They have helped us organize our leads better and keep track of what needs follow up attention from sales people.