You're waiting patiently for your flight when you hear a voice announce that they have overbooked and are looking for volunteers to take a later plane. Do you quickly raise your hand or sit still? It all depends on how quickly you need to get to your destination and what kind of compensation they are offering.

Whatever you decide, know that when it comes to airline bumping - voluntary or involuntary - while it is not illegal, you do have rights as outlined by the Aviation Consumer Protection Division of the U.S. Department of Transportation (DOT).

Voluntary Bumping

In an effort to protect against passengers who don't show up for their flight, airlines will overbook. When this happens, passengers who are not in a rush to reach their destination are voluntarily asked to give up their seat in exchange for compensation.

If you (or your boss) decide to voluntarily give up your seat, you should ask:

• For the next flight on which the airline can confirm your seat. Be careful not to be placed on standby on another full flight or you may be stranded.
• If the airline will provide free amenities such as meals, hotel room, phone calls or ground transportation, so you don't have to pay out-of-pocket while you wait for your next flight.
• How much they are paying volunteers. Airlines may negotiate with voluntarily bumped passengers and will want to get back the reservation at the lowest price.

Very often airlines will offer a free ticket, but make sure to ask about restrictions such as how long it is good for, if there are blacked-out dates, if it can be used for international flights, and how far in advance are you allowed to make a reservation.

Involuntary Bumping

While the DOT doesn't control voluntary bumping arrangements, when it comes to involuntary bumping, they require that you be provided a written statement describing your rights and explaining how the airline decides who gets bumped. You are also entitled to compensation based on the price of your ticket and the length of your delay.

If you are involuntarily bumped, the airline owes you:

• Nothing, if they arrange for other transportation that is scheduled to arrive at your final destination within an hour of your original scheduled arrival time.
• An amount equal to your one-way fare ($400 maximum), if they arrange for other transportation that is scheduled to arrive at your final destination within one and two hours after your original scheduled arrival time.
• Two times your one-way fare ($800 maximum), if they arrange for other transportation that is scheduled to arrive at your final destination more than two hours later than your original scheduled arrival time.

In addition, you keep your original ticket and use it on another flight. Or you can request an involuntary refund. Keep in mind to be eligible you must have a confirmed reservation in writing, meet the airline's deadline for buying your ticket and meet the airline's check-in deadline.

The check-in deadline varies with each airline and can mean arriving at the departure gate ten minutes to three hours before scheduled departure (depending on if it is a domestic or international flight); arriving at the ticket counter by this time; or be in the boarding area by this time.

Protect Yourself

The best way to protect yourself from being bumped is to:

• Get to the airport early since most airlines will bump passengers with lowest fares first. So for passengers in the same fare class, those that check in last are usually bumped first.
• Check-in online and get an advance seat assignment. 
• Know your rights both as a voluntarily and involuntarily bumped passenger.

By the way, according to The Consumerist the worst times for bumping are Sunday night, Monday morning, Thursday night and Friday morning, especially on heavily traveled routes like NYC to LA.