But then the kids have to be shipped off to school, Junior has a runny nose, the laundry has to be done, jobs are stressful, and then at the end of the day all you wanna do is sink into the oblivion of the television and sleep. Sex isn't on the menu -- or if it is, it's buried somewhere beneath desserts and beverages.

A recent study of couples revealed that the not-so-smug marrieds surveyed averaged 66 times per year when it came to sexual congress. Faced with a similar statistic in their relationships, two American authors recently decided to do something about their respective situations. In 365 Nights: A Memoir of Intimacy (Berkley Books), Charla Muller chronicles (in G-rated terms) what she calls her "crazy adventure" -- intimate relations with her husband Brad every day for a year.

Douglas Brown's Just Do It (Crown, an imprint of Random House) tells of the more modest goal set by he and his wife Annie: sex for 101 days straight.

"I don't think anybody enters into marriage and thinks it's going to be a sexless marriage," says Muller, reached at her North Carolina home. "Everybody thinks, 'We're not going to be that stereotypical couple who sits across from each other at dinner out and doesn't speak. We're not going to be one of those couples that blows off friends and family to get an infant in bed by dusk. We're going to be this new, enlightened couple that always puts each other first.' And then I realized that I was comically and ridiculously like everyone else."

Reached at the headquarters of the Denver Post, where he is a features writer, Brown agrees that something must be in the air for two such books to be written and published almost simultaneously.

"Maybe it has something to do with Generation X," says the 42-year-old who, like Muller, has two kids. "A lot of them are parents now, and this book has something to do with that, having sex while being a parent. It also has to do with the culture, which has become more liberal in general. Maybe the Gen-Xers are the first ones to say, 'I'm middle-aged now, and sex is great. I'm not really happy with it fading because I've turned 40 or whatever. And I'm willing to do what it takes to bring it back.'"

And because many have seen the wreckage of divorce, they are savvy enough to be scared of the sexless marriage. "They've seen marriages dissolve over and over again, and they're smart enough to realize sex is important, and if that goes away it's not good for a relationship," Brown says. "And they've seen how messy divorce is, and they don't want that to happen."

The books, and the marriages, are quite different -- but both authors are self-deprecating when it comes to what they know, thought they knew or had yet to learn. And one thing both Brown and Muller realized was that they had to prioritize with their partners. Chemistry is ideal, but sometimes you still have to plan.

"If it's fading and not happening as much as you want, and you're thinking 'Oh, the chemistry isn't happening,' you need to stand back and say, 'Chemistry is great, but I still want to do it regardless,'" says Brown.