Back when I was a financial journalist, no one asked me if I had ever traded derivatives or shorted a stock. But in my new incarnation as a chronicler of global infidelity, my own experience with the subject seems to be my chief credential. Reviewers of my book, Lust in Translation, have routinely asked what my choice of topic says about my own marriage.

''How's it going?'' an interviewer for a highbrow morning show asked bluntly.

''So far, so good,'' I responded. Soon after, I heard from colleagues, friends and long-lost acquaintances, wondering whether my relationship was on the rocks. ''Next time you are asked how your marriage is going, a simple 'great' would probably work,'' a friend from university advised.

For the record I am happily married, and my husband takes great pleasure in telling people that his wife is an ''adultery expert.'' But I drew the line when the editor of an American magazine asked to run our wedding photo alongside a story about the book. And when strangers ask what I do, I try to sound vague. I told the French photographer sitting next to me on a flight that I write about marriage. Still, I was more direct than my late grandmother, who told her elderly Canasta partners: ''It's a book about love.''

What's a girl to do when she's asked to talk about adultery live on Al-Jazeera International? I wore a shapeless turtleneck, read up on infidelity in the Muslim world, and practiced replacing my usually gleeful descriptions of global infidelity with a disapproving scowl. But instead of moralizing, the interviewer pressed me for the secrets of Japanese sex clubs and philandering Frenchmen.

There was a brief attempt to make me a pin-up girl for the cause. The Independent (UK) anointed me ''Mrs. Infidelity.'' The Observer said I was the sort of ''yummy mummy'' who might ''set up a stall in a farmers' market selling fashionable cupcakes.'' But the magic fizzled when the paper hired a famous Brazilian photographer to take my picture. He took one look and decided I should pose directly behind a large plant.

Given the current political climate, I think foreign reporters liked the fact that I was an American criticizing my own country, for its odd rules of fidelity. They called from all over the world, often looking for a unique angle. An Argentine reporter wanted to know if there might be a connection between adultery and global warming.

Americans had the strongest reactions to the topic. Though I never claimed to have written a self-help book, some reviewers on posted warnings, such as “Please do Not look to this book for help . . . Do Not Trust Pamela Druckerman.” On tour back home, I was frequently mistaken for someone with actual wisdom to dispense. In Miami, a woman pressed me for details about exactly what kind of men were most likely to cheat (a 40-year-old traveling salesman from Togo, I concluded helpfully).

At least I've developed good radar for whether a person cheats. Just mentioning my topic -- once I actually do -- is a kind of litmus test. The faithful types usually feel safe asking follow-up questions. But those with secrets just say ''huh!'' and change the subject.

Author's Bio: 

Pamela Druckerman is the author of Lust in Translation: Infidelity from Tokyo to Tennessee.