T+L’s personal finance columnist, Jean Chatzky, answers your questions. This month: The tipping points.

Q: My husband and I have an ongoing disagreement about tipping, whether we're traveling or simply eating at a restaurant. I believe in tipping well because I think it helps ensure better service, and because, to be honest, I feel bad when I'm not generous. He believes tipping in general has gotten out of control, so he sticks to 15 percent and often grumbles about that. Who's right?Who's wrong?—Name withheld, Dallas, Tex.

A: You are both right, but you're also both wrong. Let me clarify. Your husband is absolutely correct in noticing that there's been an increase in tipping of late. Michael Lynn, associate professor of marketing at the School of Hotel Administration at Cornell University (and a psychologist by training), has studied tipping extensively, and he says that in the 1950's, people would tip 10 percent on average. In the 1970's and 1980's, that number climbed to 15 percent. Now, the number is closer to 19 percent.

Big tippers are raising expectations People are tipping more and bringing up the average expected amount. Lynn explains that some people (like you) tip out of a desire to be generous, to take care of or help out another person. Most people, however, tip to raise their social status or avoid social disapproval, or (like your husband) they feel guilted into it. The former two categories explain why people tip more today: if I tip more, they reason, the server and those around me won't think less of me. With everyone tipping more than the average, over time, that average goes up.

Tipping well doesn't ensure great service You have to remember that, in most cases, you don't tip until after your bags have been carried to your hotel room, your wine selected for dinner, your massage completed at the in-house spa. Although tipping generously at a restaurant or salon that you visit regularly may result in better service, you can't make that argument when you're traveling somewhere for the first time.

It's more than money Seattle-based etiquette coach Stephanie Horton (who runs TopDogEtiquette.com) suggests applying a "verbal tip" from the beginning: "If you want to get good service, you have to treat servers of all types the way you want to be treated," she says. "Give them a warm greeting, look them in the eye, say thank-you for the first thing they do for you. That sets the stage." Michael Lynn's studies have shown that factors besides good service can affect the size of a tip a customer leaves—sunny weather, for example. But even acknowledging external factors and following a few simple recommendations may not be enough to put an end to your tipping squabbles. According to Horton, your husband should stick to 15 percent. And sneaking a few extra dollars onto the restaurant table or the bureau for the chambermaid while your husband isn't looking may not be the best idea either. (See the Friends episode in which Ross pads the meager tip left by Rachel's notoriously cheap father for an indication of what can ensue.) Instead of working against each other, here is what I would like you to try:

Know what's expected Web sites such as Tipping.org and Magellans.com have a great deal of information on tipping customs around the world. In Italy and Mexico, for instance, 10 percent is quite adequate; in Turkey, you can just round to the nearest lira; and in Vietnam, tipping is illegal. (Maybe your husband should vacation there.) Make sure you and your spouse are also clear on the difference between a service charge (which may or may not get into the hands of your actual server) and a tip (which does).

Consider a cruise or resort, where service charges are built in There may be more ways than you think to vacation or travel without having to deal with this issue at all. For example, both Norwegian and Holland America lines automatically add a $10-a-day charge to the bill (adjustable at the guest's discretion). And on Silversea, all gratuities are included.

Share the responsibility of paying (and tipping) If you're headed to a destination where tipping is expected, strike a deal with your husband that you'll handle the money one day and he'll be responsible the next. On your days, tip as generously as you want. On his, he can add what he considers appropriate. And you'll both get a much-needed break.

Ask Jean! Send your queries about value-related travel issues to AskJean@aexp.com. We regret that questions can be answered only in the column.