Chats and Forums
Adult Twins, All Twins Here, Facts About Multiples Board, Fraternal Twins, Homeschooled Twins, Multiples Outlet Forum, Names for Multiple Births, Scrapbooking Twins, Twin Talk Bulletin Board, TWINteresting
Conjoined Twins
Bijani, Laleh and Ladan, Chats and Forums, Headley, Dao and Duan, Hensel, Abigail and Brittany, Ibrahim, Mohamed and Ahmed, Jodie and Mary, Quiej Alvarez, Maria Teresa and Maria de Jesus, Schappell, Lori and Reba, Smith, Victoria and Brynleigh, Turner, Iesha and Tiesha
Conventions
International Twins Association Convention, Michigan Twins Association, NOMOTC Annual Convention, Pleucadeuc, The Triplet Connection: Annual Convention, Twins Days - the Unofficial Homepage, Twins Days Official Web Page, Twinstuff.com - Twin Events
Literature
Brookline University, Julia and Robbie: The Disaster Twins, Mirror Images, Sandy Cove, The Carlson Septuplets, The Clorenson's, The Highland Triplets, The Lost Sisters, The Sky's The Limit, Triplet Tales
Parenting
Chats and Forums, Clubs, About.com: Parenting of Multiples, All Info About Parenting Multiples, American Baby: Parenting Twins and Multiples, GotTwins.com: Detailing Life With Twin Boys, Home Schooled Multiples, Just Ask Freda, KeepKidsHealthy.com: Twins, Mom2Many.com - Parents of Multiples Across Canada, MOST: Mothers of Supertwins, Multiple Births Canada
Research
Australian Twin Registry, International Society for Twin Studies, Millennium Twins, Northern California Twin Registry, The Center for Study of Multiple Birth, The MIT Twins Study Homepage, Twin Research, Twin Research, Twin Research and Genetic Epidemiology, Twin Studies
Twin Loss
A Different Kind of Grief, Center for Loss in Multiple Birth (CLIMB), Inc., CLIMB: Saint Louis, Missouri, eLIMBO, European Twins Support Group, Loss Of A Twin Or More, Murraylands Lutheran Stillborn Infant Support Serv, My Angel Son's Callum and Kye, Twin Boys, Twinless Twins
Facts About Multiples
Information on twins, triplets, quadruplets, quintuplets and higher order multiples. Features a database of multiple birth families, statistics, basic information on twinning, world records and information on fakers.
The Center for Study of Multiple Birth
A resource for research and information about the causes, effects and problems of multifetal pregnancy.
The International Twins Association
A non-profit, family-oriented organization to promote the spiritual, intellectual, and social welfare of twins and multiples throughout the world.
TwinMajority.org
From 2127, most babies will be twins. This site explains why evolution predicts this.
Twins by Twins
This site is built for all those that want to learn more about twins and is dedicated to those that are twins and proud of it.
Twins Network
A resource for understanding twins and sharing information. Surveys, facts, news, trivia, links.
TwinStuff.com
Bulletin boards, twin games, photo gallery, information for parents, TV and movie twins, twin events, and information.
Twinsworld
Offerings include a twin casting agency, twin events, reunion of twins placed for adoption or separated at birth, message boards, links, photos, contests, and research.