How do I sync my iPhone contacts to my Outlook contacts?

I just bought an iPhone 4S and got all my contacts transfered over to the new phone. I would now like to have all of those contacts in Outlook and be able to organize them in outlook. Can I do this? I have my Outlook account on the iPhone and as far as I can tell my iPhone contacts should show up on my Outlook contacts. I've made 1 new contact since I've had the iPhone and it did show up in my Outlook contacts, but this is the only one. Thanks for your help!