4) "What if we have a date, and I'm not in the mood?" Lower-desire partners always ask this question, but the issue usually turns out to be less problematic than they fear. As scheduling reduces tension over sex, the relationship improves. This makes it more natural for the lower-desire partner to get psyched for sex.

No sex schedule can be carved in stone, of course. Try scheduling sex dates for six months or so, sex therapists advise. If that's not working, renegotiate.

5) Stick to your "encounter calendar" in good faith. Don't bicker about your compromise schedule. Higher-desire folks must not whine for more sex. Lower-desire partners must not cancel sex dates — or postpone them unreasonably.

6) Cuddle up. When couples adjust to scheduled trysts, nonsexual affection returns to the relationship. And with both parties aware of the calendar of upcoming events, either one can initiate hugging, kissing or cuddling without fear of misinterpretation. Couples who resolve their desire differences often marvel at how much they've missed nonsexual affection, even as they rediscover how crucial it is to the relationship — and to their own well-being.

7) Consider talking it out with a pro. If you need help negotiating a schedule, or if a chronic desire difference has undermined your relationship to the point where you can't discuss the issue, consult a sex therapist. To find one near you, visit the American Association of Sexuality Educators, Counselors and Therapists; the Society for Sex Therapy and Research; or the American Board of Sexology. Figure four to six months of weekly hour-long sessions.

A sex educator for 40 years, Michael Castleman, M.A., publishes GreatSexAfter40.com.

Also of Interest

• 7 ways to protect your marriage from infidelity
• 5 foods that whiten your teeth naturally

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