Over the past number of years, baggage fees have been incorporated as an additional means of revenue for the airlines. Every airline has a different policy, which can be not only daunting, but confusing.

1. Baggage fees are per bag and per direction. So one way = one charge. Round trip = two charges. If your flight has a connection, bags will usually transfer from flight to flight and no additional fees will apply. There are a few exceptions, rare but possible: If you purchase separate tickets for each leg of your journey, and if you are connecting to another airline and the first airline and the second don`t have a baggage agreement with each other, then you will have to grab your luggage at the connecting airport and go through the check-in and security process all over again.

2. Currently, international (`over the water` and/or `long-haul`) flights will allow for one piece of luggage per person, up to a certain size and weight (varies by carrier) free of charge. Domestic flights within the US (unless they are feeding into a long-haul flight on the same itinerary) will charge you for any checked-in luggage. A lot of `short-haul`, `point to point`, inter-city flights within Europe, Asia, etc are following the domestic flight model and will now charge for any checked luggage.

3. Do remember that these charges are set by the airline, and you won`t find a difference in price whether you purchase your ticket online, over the phone, through the airline at the airport, or through TripMasters. The bag charge will be the same regardless.

4. Most airlines will not charge bag fees for the following groups of people: frequent flyers (or those with `elite` status with the airline); first and business-class ticketholders; ticketholders who purchase refundable fares; U.S. military active-duty members (and sometimes their dependents); and, in many cases, even card holders of the airline`s credit card.

5. Baggage fees are based on weight, size, and the number of pieces checked. Bags over 50 pounds are usually considered `oversized` and will incur an extra fee. Extra fees will also occur if the bag checked exceeds the dimensions set forth by the airline, or if you have more than one bag to check.

IMPORTANT: In order to make your trip as easy and painless as possible, TripMasters will purchase seats for you on airlines that charge extra fees for seats on short-haul, point to point fares. Unfortunately, the airlines are very dynamic and are constantly changing their policies, so the possibility of us being unable to purchase seats for you ahead of time is a real one.

Take some time to look at your airline voucher; when we have purchased a seat for you, you will usually find that it clearly indicates `1ST CHECKED BAGGAGE PAID UP TO 23kg`.

For the few flights that will not include such a comment in your voucher, we strongly recommend that you visit the website for the airline in question (as you would do for checking in) a couple of days before your flight. While there, check to see if you need to pay for baggage. Many times, it is cheaper to prepay online than to wait and pay at the check-in counter at the airport.

Nowadays, many travelers bring their bags on board with them to avoid bag fees. Usually, that is a good idea, since nearly every airline allows for one free carry-on bag based on size and weight constraints (typically fewer than 45 linear inches and less than 30 pounds). Keep in mind that a few airlines (such as Spirit and Allegiant) will actually charge you for your carry-on at a price even higher than a checked bag. All airlines, including Spirit and Allegiant, do allow you to bring a `personal item` on board such as a purse or a laptop for free, however.

Airlines are amenable to paying for `reasonable expenses` until your baggage is found, should the pieces be lost for whatever reason when you reach your destination. The amount must be negotiated and you may have to be quite assertive to get your share. If your bags are not recovered, you can file a claim, and that will take a little while to process. Depending on the airline, you can wait weeks, even months, for reimbursement. Take note of deadlines as well: If you missed the check-in deadline at your home airport, the airline will not have to reimburse you if your bag is delayed or lost. International treaties spell out liability limitations for airlines if bags are delayed or lost overseas.

The first thing to remember is not to panic if your bags end up delayed. The airlines can track most lost bags, and those tracked bags will eventually be returned. If your bags end up on the next flight out, that means you will only be separated from them for a few hours. A serious mix-up would involve the bags being sent off to a different airport, in which case it may take days for you to be reunited with your luggage. File your claim right at the airport as soon as you notice your bags are not on the carousel. Give the attendant a valid address and phone number so you can be reached in the event that your bags are eventually returned to you.

It is very rare that the airlines will ask you to pick your luggage up from the airport; they will usually return it directly to you. Also, many airlines will reimburse you for any last-minute expenses accrued by the temporary loss of your luggage. Keep your receipts handy!

Jot down a reference number before you leave the airport so you have it to follow up on your claim. You will also use this number to check on the status of your bags. Some airlines offer a telephone-centric system and others allow you to check the bags` status online.

According to a recent FAA reauthorization bill, you will be entitled to a refund of any checked baggage fee you paid if your bag or bags are lost longer than 12 hours after reaching your destination (15 hours for international flights).

File a written claim for damages if your airline loses your bags. This form may be different than the `missing luggage` form, so inquire. This form can be filled out directly at the airport or it can be filled out later and mailed.

$3,500 is the largest amount an airline will pay to cover lost bags and their contents on domestic flights in the U.S. A varying rate per passenger is used for bags lost on international flights, based on amounts pre-determined in the Warsaw Convention or the Montreal Convention. In the U.S., if you paid to check your bags with an airline and they are lost, the airline must refund that fee to you. Go to the airline`s website to read more information about their baggage regulations.

In some cases, the value of certain items in the suitcase may be called into question and in these cases you may be asked to prove the item`s price; if you have any receipts handy, keep these in the event that you are asked for them. (The airline will then decide on a depreciated amount to pay you -- you won`t get retail prices for used items.) `Excess valuation` protection is available if the items in your checked baggage are quite valuable, but only purchase this protection if the items aren`t already covered by your home or travel insurance. TripMasters` trip insurance covers lost and delayed baggage.

The airlines usually have a specific list of items for which they will not be held liable in the case of lost or stolen baggage. Money, heirlooms, and jewelry are usually on every airline`s list. Pack these items in your carry-on and consider leaving as many as possible at home.

To minimize the amount of time in which your bag can be snatched by an unscrupulous passerby, head to the baggage carousel as soon as you get off the plane. Most airlines keep records of bags as they are processed and then sent to baggage claim. If the airport finds that the bag was stolen after it was checked in at the airport, you must now file a claim with the police as the airline is no longer liable. Consider purchasing travel insurance; home insurance may cover stolen baggage but it doesn`t always.

Check your bags for damage, tampering or other issues as soon as you grab them off the carousel. Make sure you report any damage before you leave the airport. Airline employees will want to take a cursory inspection of the damaged bags in question. Minor wear and tear will not be covered by most airlines. Ask the baggage claim attendant which repairs are covered and not covered by the airline; you will need to save your repair receipts to get compensation.

1. Write your name, address and phone number on two labels. Place one inside your bag and one on the bag or tied to the bag handle. Also something to consider is the option of placing your itinerary inside your bags, so the airline will have an easy time locating you.

2. Late check-ins and tight connections are the two biggest reasons bags end up arriving late or not at all. Avoid both of these factors at all costs.

3. All valuable items, such as passports, money, jewelry, heirlooms, etc. should be packed inside your carry-on bags, NEVER your checked luggage.

4. Make a list of everything you packed before you travel. Airlines will want to know what all was lost in your bags should they need to reimburse you.

5. Double-check your bags and make sure the destination tickets on your bags match the airport at your destination. Get a claim ticket for each bag.

6. If your checked bag is delayed, you will be so thankful that you did this: Pack a change of clothes in one of your carry-on bags. If you are traveling with a significant other, consider swapping some of your clothing to your partner`s bag, and vice versa, so you have at least a limited wardrobe should one of your checked bags be delayed or lost.

7. Buy travel insurance. If you lose anything, having purchased travel insurance will turn out to be very important, especially when it comes time to file for reimbursement.

8. Services such as ReboundTAG or SuperSmartTag offer luggage tags which are printed with serial numbers. These numbers are registered on an online database, and if a bag is lost, the owner can be found with a simple database search. The services will contact you as soon as your items are found and reported.

Also, check out UnclaimedBaggage.com...the final resting place for many lost bags!