Homeowners insurance, car insurance, health insurance -- all policies designed to help you in the event of trouble.

But what about travel insurance? When does it make financial sense to protect your next trip?

You wait all year for that fantastic vacation to a faraway place -- or even to visit grannie in California -- and something happens and you just can't go.

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You may think the airlines will simply re-fund your money, but it usually doesn't work that way -- and that where travel insurance can pay off.

"We were going to a Navy convention in September," said Joyce Barnowski.

Barnowski booked two airline tickets for herself and a friend back in August. Each ticket for their flight cost almost $400.

But three weeks before their trip "I got a call from his son saying Carl was in a nursing home under doctor's care, and could not make the trip."

Despite her efforts, including sending a doctor's note to the airline, she couldn't get a refund on her tickets, and Joyce didn't have travel insurance.

"I let them know three weeks in advance and I did everything in my part and I'm terribly disappointed in the airlines," Barnowski said.

"The only option airlines will give them is to take care of credit forward unless it was a non-refundable and non-transferable ticket," said Steve Danishek, a travel agent.

Danishek said travel insurance covers your losses if you miss your flight, or your trip is delayed or interrupted.

But he says the most significant cost travel insurance covers is medical emergencies.

"If you break your hip in Panama and have to be flown back to Seattle, that's a $30,000 private air ambulance bill, and that's cash and that's a lot of money," Danishek said.

So you've saved all year for that dream vacation. Do you spend the extra money to insure it?

"You don't have to buy much to get a lot of the benefits, but you should have some," he said.

One thing to keep in mind: Travel insurance is good for one year from the time it was purchased, not a year from the time you travelled.