We use Quickbooks Pro 2002. I couldn't run without it. But be Careful, you must use all features of it or your balances will be way off. for example if you use it to bill and receive payments but not for banking than you will show all kinds of money in a Quickbooks default account called undeposited funds. so if you try to run a balance sheet it will show that you have x amount of money in some un-known account which a bank or the IRS is going to ask you to prove where this money went and it's a hassle. Also if you are in a state where you collect sales tax on the services you perform, you must use the pay sales tax function and not just write a check out from the check reg. I had an Office manager do that for over a year and i am still paying for that mistake with St. Revenue Dept. Bottom line is use every feature and it runs your business smooth. That has been my experience with it.