In general, I try and make all of my purchases on one credit card, and only use my debit card for withdrawing cash at atm's. That way I only have to monitor one account for fraudulent activity. Where this breaks down, is a lot of the discount/cheaper gas stations will only accept cash or debit. Also, the magnetic stripe seems to wear down pretty fast on my cards, which means I often have to use my debit card when the credit card isn't swiping. I agree though, get a credit card (preferably with rewards, mine does 1% cash back) and use that for all of your purchases.