Short Sales, "short selling", "shorting", Short Payoff, Pre-Foreclosure Sale, or Comprmise of Sale happens when a lender agrees to accept less than the amount owed against the home because there is not enough equity to sell and pay all costs of sale. In a nutshell it is asking the bank for forgiveness and to let you go with just a slap on the hand.
Not all lenders will negotiate a short sale, and that is why a real estate agent can be a tremendous help by contacting the lender's loss mitigation department to find out. In the past I have witness the borrower being treated differently than that of a third party intervention.
You can't just wake up one morning and decide, "Hey I'm going to sell your home at a loss by asking for a short sale." Typically, lenders won't even consider a short sale unless payments are in arrears. Lenders will be more agreeable to negotiation if your payments are delinquent which is sad to say but true. Which I am not advising for one to be late on their payments. But just know your options so when your decision is made it will be a right one for you.
There are many other per-foreclosure options that you may qualify for but you have to inform yourself of all the option before make a decision. Visit www.NLMloanmod.com