(FORTUNE Magazine) – Cruising the deep blue Pacific off Mexico, Margaret C. Whitman, 29, a management consultant with Bain & Co. in San Francisco, basked by a pool on Sitmar Cruises' luxurious Fairsky while her 11-month-old son, Griffith, scrambled around the playroom three decks below. Watched over by one of the ship's trained counselors, ''Griff'' was among 20 passengers under age 2. Later, refreshed and relaxed, his mother took him to the children's pool, where he loved the water slide. And she loved wheeling him around the promenade deck in his stroller. ''I work five days a week, and my vacation is one time I can see my little boy. Yet I need a rest, too,'' says Griff's mother, who is married to Dr. Griffith Harsh, 32, a neurosurgeon. Before the cruise with his mother and grandmother, Griff had gone with his parents on a Hawaiian vacation. His mother explains, ''My husband's idea of a vacation is to see his son. And most of my friends feel they don't want to take a vacation without their children, especially if both parents work.'' Many young parents these days feel like Griff's. The parents of the current baby boomlet are more likely than any previous generation to be two-career couples, so their vacations do double duty: they should let Mom and Dad unwind and also provide valuable time with the children. Several travel companies offer vacations that do both. Griff's mother chose a cruise because she found on the Hawaiian trip that moving moppets around is tough. And, she says, ''kids like the routine of one place.'' She chose Sitmar because its ships offer separate child and teen centers staffed from 9 A.M. until midnight, and its playrooms are well stocked with books and toys. Three Sitmar ships ply the Caribbean and the Pacific. During the off-peak period from September to early December, a nine-day cruise from Los Angeles to Acapulco and back in an outside cabin costs $2,075 per adult -- an inside cabin is $1,675 -- plus $420 per child sharing a cabin with two adults. Prices include round-trip air fare from more than 140 cities. Lower fares may be available through travel agents. Finding trips or resorts with programs for children under 3 is not easy. Even Florida's Walt Disney World requires that children left at its KinderCare Children's Center or Mouseketeer Clubhouses be toilet-trained; it minds fewer than 50, and only on weekends and evenings. Several ski resorts welcome the extremely young, including Copper Mountain, Keystone, and Vail in Colorado, and Grindelwald and Zermatt in Switzerland. THE TINIEST HEDONISTS are also welcome at some Club Meds. The swinging singles who once peopled the resorts are growing up, so Club Med now urges parents to bring infants as young as 4 months to Baby Clubs. In the Bahamas, Paradise Island will welcome them from May through October. On Eleuthera, a Mini Club takes children 2 to 11. Stephanie Weisser, 34, and husband Paul, 32, part owners of Mother's Restaurant in New Hope, Pennsylvania, spent a week there in March with son Zachary, 2. Mornings the Weissers played tennis, snorkeled, and sailed. A G.O. (gentil organisateur, as Club Med calls members of its staff) took Zachary and a half dozen other toddlers to the beach or to the playground and gave them lunch and a nap. Afternoons the Weissers played with Zachary, then gave him supper in the children's section of the dining room. They put him back in the Mini Club from 7:30 to 9 while they ate dinner. ''We had a wonderful time,'' says Stephanie Weisser, ''but I wouldn't do it again with a child Zachary's age.'' He had a hard time adjusting to a new schedule and new people. Club Med works better for gregarious older children, who on Eleuthera can learn trapeze performing, among other things. A week at Eleuthera's Club Med, including air fare from New York, costs $780 to $1,300 per adult depending on the season. Accommodations cost about 50% less and air fare 25% less for children under 12 (800-258-2633). Dude ranches corral riders as young as 5 and 6. At the Tanque Verde Ranch 12 miles east of Tucson, children eat all meals and ride twice a day with counselors. On a recent visit, Robert Simmons, 40, a vice president at Manufacturers Hanover Trust Co. in New York, and wife Margaret, 43, an editor at Connoisseur magazine, went trail riding while Edward, 5, and Jane, 6, learned to ride in an arena. At week's end the kids took a five-hour trail ride with their counselor and won ribbons at a kids' rodeo. The ranch, with 60 guest rooms and over 100 horses, also has five tennis courts and two swimming pools. When counselors are available, from December through April, rates run $170 to $215 per couple per day plus around $50 per day for each child staying with the parents, including meals and all activities (602-296-6275). Other choices range from bucolic to exotic. Robert Mitchell, 34, corporate controller of Scholastic Inc. in Lyndhurst, New Jersey, and his wife, Shay, 34, take their girls to James and Nancy Rodgers's dairy farm in West Glover, Vermont. On their first visit, Kate, 2, learned to gather eggs, and Keri, 5, watched a newborn calf with its mother. Cost: $550 a week for the family of four, with shared bath and all meals (802-525-6677). In Nepal, families can trek near Mount Everest at heights up to 12,800 feet for ten days. Small children can ride in a basket on a porter's back. One of three annual family adventures -- the others are in Kenya and Peru -- arranged by Mountain Travel of Albany, California (800-227-2384), the Nepal Trek costs $1,570 per adult, about half that for children ages 2 to 14, not including air fare. A number of European organizations cater to vacationers with youngsters. Switzerland's Happy Family Hotels, which say they are kinderfreundlich (child friendly), offer playrooms and free care for children 3 and up; attendants in major resort areas speak English. The Swiss National Tourist Office (212-757-5944) has details. London's Universal Aunts (01-351-5767) will take children sightseeing. For simple babysitting in Britain, Babycare Childminders (01-935-9763) is reliable and reasonably priced. For the planning essential to a good time with kids, guidebooks pile high. Traveling with Your Baby by Vicki Lansky (Bantam Books, $2.95) is a primer of practical advice. Fielding's Family Vacations USA by Diane Torrens (William Morrow & Co., $12.95) and the newer What to Do with the Kids This Year by Jane Wilford and Janet Tice (East Woods Press, $8.95) describe U.S. resorts with children's programs. Farm, Ranch & Country Vacations by Pat Dickerman (Farm & Ranch Vacations, $11) is a good source for rural vacationers. Fielding's Europe with Children by Leila Hadley (William Morrow & Co., $12.95) includes a country-by-country guide. For more up-to-date information, the most complete newsletter is Family Travel Times ($24 a year), a monthly published by Travel With Your Children (212-206-0688). The company also publishes annually revised directories, Cruising with Children and Skiing with Children. And if doing anything with children sometimes seems trying, remember -- as grandmother will certainly remind you -- they're not children for long.