Q. What are my rights if a piece of checked airline baggage goes missing?

A. It depends on what you mean by missing, and whether the flight is domestic or not. If the bag is lost forever on a domestic U.S. flight, then you can claim up to $3300 in compensation from the airline, but you'll have to produce receipts for the value of the bag and its contents, which is why I advise readers to save every receipt for clothing purchased. Note that "valuables" such as electronics, jewelry, antiques, cash and other similar items will not be covered by the airline (these should always go in your cabin luggage), and the airline will attempt to depreciate the value of your possessions, just as an insurance company would in the event of a loss. The rules are different for checked baggage lost on flights originating or flying to non-U.S. destinations.  Many countries and thus airlines follow a set of rules called the Warsaw Convention, which limits liability for loss or damage to luggage at  $9.07 per pound ($20.00 per kilo) for checked baggage with a maximum of $640, and $400 per passenger for unchecked baggage, unless a higher value is declared in advance and additional charges are paid. Most  travel, however, will be governed by the newer "Montreal Convention," which stipulates higher liability limits for international flights (but it's still less than domestic liability). That’s why it’s so important to buy excess valuation coverage,where available, when checking bags on an international flight. Ask about this coverage when you hand over your luggage at the airport. It's surprisingly inexpensive, ranging from 50 cents to one or two dollars per $100 of coverage. If your bag is merely "delayed" rather than totally lost, however, things get murkier. If you can prove consequential damages, the airline is still liable up to the amount stipulated above, but such damages may be difficult to substantiate. For example, if your business suit was in the delayed luggage and you were scheduled to speak at an important conference the next day but were traveling in your gym clothes, you could justifiably buy a new suit and attempt to charge the airline. However, you wouldn't want to buy a $3000 suit. Reasonable behavior is advised in such circumstances.