| T.O.P.S. (Take Off Pounds Sensibly) | |
| T.O.P.S. (Take Off Pounds Sensibly) - Overweight | |
TA | |
| 'Taking Flight' Fear of Flying Support | |
| 'Taking Flight' Fear of Flying Support - Anxiety Attacks / Phobias / Agoraphobia | |
| (TAPS) Tragedy Assistance Program for Survivors | |
| (TAPS) Tragedy Assistance Program for Survivors - Bereavement (General) | |
| Takayasu's Arteritis | |
| Takayasu's Arteritis Association | |
| Takayasu's Arteritis Association - Takayasu's Arteritis | |
| Tall Clubs International | |
| Tall Clubs International - Short / Tall | |
| TARA | |
| TARA - Mental Health Helpline | |
| TASC (The American Surrogacy Center) | |
| TASC (The American Surrogacy Center) - Infertility / Childlessness | |
| Tax Info Helpline | |
| Tay-Sachs Disease | |
TE | |
| Technical Assistance Alliance for Parents Centers | |
| Technical Assistance Alliance for Parents Centers - Disability Helpline | |
| TeenHelp | |
| TeenHelp - Youth / Students | |
| TEF/VATER Support Network | |
| TEF/VATER Support Network | |
| TEF/VATER Support Network - Tracheo Esophageal Fistula | |
| TEF/VATER Support Network - VATER Association | |
| Temporomandibular Joint Dysfunction (TMJ) |  Top |
| TerrificKidsWFA | |
| TerrificKidsWFA - Allergy | |
| Texas Heart Institute Heart Information Service | |
| Texas Heart Institute Heart Information Service - Heart Helpline | |
| Texas Self-Help Information and Education Service | |
| Texas Self-Help Information and Education Service - Clearinghouse - Texas | |
TH | |
| The Aarskog Syndrome Parents Support Group | |
| The Aarskog Syndrome Parents Support Group - Aarskog Syndrome | |
| The ACC Network | |
| The ACC Network - Agenesis of the Corpus Callosum | |
| The Arc | |
| The Arc - Mental Retardation / Down Syndrome | |
| The At Home Dad Network | |
| The At Home Dad Network - Parenting / Grandparenting | |
| The Barth Syndrome Foundation | |
| The Barth Syndrome Foundation - Barth Syndrome | |
| The Beginning Experience | |
| The Beginning Experience | |
| The Beginning Experience - Separation / Divorce | |
| The Beginning Experience - Widows / Widowers | |
| The Brachial Plexus Palsy Foundation | |
| The Brachial Plexus Palsy Foundation - Brachial Plexus Injury / Erb's Palsy | |
| The Cobalamin Network | |
| The Cobalamin Network - Cobalamin | |
| The Coffin-Lowry Syndrome Foundation | Top |
| The Coffin-Lowry Syndrome Foundation - Coffin-Lowry Syndrome | |
| The Dysautonomia Foundation, Inc. | |
| The Dysautonomia Foundation, Inc. - Dysautonomia | |
| The Erythromelalgia Association (TEA) | |
| The Erythromelalgia Association (TEA) - Erythromelalgia | |
| The Foundation Fighting Blindness, Inc. | |
| The Foundation Fighting Blindness, Inc. - Blind / Visually Impaired | |
| The Genetic Alliance | |
| The Genetic Alliance - Genetic Disorders | |
| The Gorlin Syndrome Group | |
| The Gorlin Syndrome Group - Gorlin Syndrome / Basal Cell Carcinoma Nevus Synd | |
| The HELLP Syndrome Society | |
| The HELLP Syndrome Society - HELLP Syndrome | |
| The Hyperacusis Network | |
| The Hyperacusis Network - Hyperacusis / Sensitive Hearing | |
| The International Morquio Support Group | |
| The International Morquio Support Group - Mucopolysaccharidoses / Morquio's Syndrome | |
| The LAM Foundation | |
| The LAM Foundation - Lymphangioleiomyomatosis | |
| The Living Bank - National Organ and Transplant Registry | |
| The Living Bank - National Organ and Transplant Registry - Organ Donation Helpline | |
| The Lupus Foundation of America, Inc. | |
| The Lupus Foundation of America, Inc. - Lupus | |
| The M.I.S.S. Foundation | |
| The M.I.S.S. Foundation - Death of a Child / Fetal Loss | Top |
| The Mastocytosis Society | |
| The Mastocytosis Society - Mastocytosis | |
| The MHE Coalition | |
| The MHE Coalition - Multiple Hereditary Exostoses | |
| The Myositis Association | |
| The Myositis Association - Myositis | |
| The National Fragile X Foundation | |
| The National Fragile X Foundation - Fragile X Syndrome | |
| The Panic Center | |
| The Panic Center - Anxiety Attacks / Phobias / Agoraphobia | |
| The Phoenix Society for Burn Survivors, Inc. | |
| The Phoenix Society for Burn Survivors, Inc. - Burn Survivors | |
| The Pull-thru Network | |
| The Pull-thru Network | |
| The Pull-thru Network | |
| The Pull-thru Network - Anorectal malformations | |
| The Pull-thru Network - Incontinence | |
| The Pull-thru Network - Ostomy | |
| The Romberg's Connection | |
| The Romberg's Connection - Parry-Romberg Syndrome | |
| The Selective Mutism Group | |
| The Selective Mutism Group | |
| The Selective Mutism Group | |
| The Selective Mutism Group - Anxiety Attacks / Phobias / Agoraphobia | |
| The Selective Mutism Group - Families of Mentally Ill | Top |
| The Selective Mutism Group - Selective Mutism | |
| The Self-Help Clearinghouse (Rockland County) | |
| The Self-Help Clearinghouse (Rockland County) - Clearinghouse - New York | |
| The Self-Help Connection | |
| The Self-Help Connection - Clearinghouse - Canada | |
| The Sturge-Weber Foundation | |
| The Sturge-Weber Foundation - Sturge-Weber | |
| The Support Network - Edmonton's Distress Center | |
| The Support Network - Edmonton's Distress Center - Clearinghouse - Canada | |
| The Triplet Connection | |
| The Triplet Connection - Death of a Child / Fetal Loss | |
| The VATERS Association Family Network | |
| The VATERS Association Family Network - VATER Association | |
| Think First National Injury Prevention Foundation | |
| Think First National Injury Prevention Foundation - Trauma Helpline | |
| Through the Looking Glass | |
| Through the Looking Glass - Disability Helpline | |
| ThyCa: Thyroid Cancer Survivors' Association, Inc. | |
| ThyCa: Thyroid Cancer Survivors' Association, Inc. | |
| ThyCa: Thyroid Cancer Survivors' Association, Inc. - Cancer | |
| ThyCa: Thyroid Cancer Survivors' Association, Inc. - Thyroid | |
| Thyroid | |
TM | |
| TMJ Association | |
| TMJ Association - Temporomandibular Joint Dysfunction (TMJ) | |
TO | |
| Toastmasters International | Top |
| Toastmasters International - Speech / Stuttering | |
| Totally Hip | |
| Totally Hip | |
| Totally Hip - Hip Replacement | |
| Totally Hip - Orthopedic (knee, hip, back, shoulder) | |
| Tourette Syndrome | |
| Tourette Syndrome Association | |
| Tourette Syndrome Association - Tourette Syndrome | |
| Toy Safety Hotline | |
| Toy Safety Hotline - Consumer Helpline | |
TR | |
| Tracheo Esophageal Fistula | |
| Tracheostomy | |
| Trafficking in Persons and Worker Exploitation Helpline | |
| Trafficking in Persons and Worker Exploitation Helpline - Crime Victims Helpline | |
| Tragedy Assistance Program for Survivors (TAPS) | |
| Tragedy Assistance Program for Survivors (TAPS) - Veterans / Military | |
| Transplant Recipient, Organ | |
| Transportation Helpline | |
| Transverse Myelitis | |
| Transverse Myelitis Association | |
| Transverse Myelitis Association - Transverse Myelitis | |
| Trauma | |
| Trauma Helpline | |
| Treacher Collins Connection | |
| Treacher Collins Connection - Treacher Collins Syndrome | Top |
| Treacher Collins Syndrome | |
| Trefpunt Zelfhulp | |
| Trefpunt Zelfhulp - Clearinghouse - Belgium | |
| Trichotillomania Learning Center | |
| Trichotillomania Learning Center - Obsessive-Compulsive Disorder | |
| Trigeminal Neuralgia / Tic Douloureux | |
| Trigeminal Neuralgia Association | |
| Trigeminal Neuralgia Association - Trigeminal Neuralgia / Tic Douloureux | |
| Trimethylaminuria Support Group | |
| Trimethylaminuria Support Group | |
| Trimethylaminuria Support Group - Metabolic Disorders | |
| Trimethylaminuria Support Group - Odor (Body / Breath) | |
| TRIO (Transplant Recipients International Organization) | |
| TRIO (Transplant Recipients International Organization) - Transplant Recipient, Organ | |
| Triple X Support Group | |
| Triple X Support Group - Triple-X Syndrome | |
| Triple-X Syndrome | |
| Triplet Connection | |
| Triplet Connection - Twins and Triplets | |
| Trisomy | |
| TRUE Kids | |
| TRUE Kids - Urea Cycle Disorders | |
TU | |
| Tube Feeding | |
| Tuberous Sclerosis | |
| Tuberous Sclerosis Alliance | Top |
| Tuberous Sclerosis Alliance - Tuberous Sclerosis | |
| Turner Syndrome Society of Canada | |
| Turner Syndrome Society of Canada - Turner's Syndrome | |
| Turner Syndrome Society of the U.S. | |
| Turner Syndrome Society of the U.S. - Turner's Syndrome | |
| Turner Syndrome Support Network | |
| Turner Syndrome Support Network - Turner's Syndrome | |
| Turner's Syndrome | |
TW | |
| Twin to Twin Transfusion Syndrome | |
| Twin to Twin Transfusion Syndrome Foundation | |
| Twin to Twin Transfusion Syndrome Foundation - Twin to Twin Transfusion Syndrome | |
| Twinless Twin Support Group | |
| Twinless Twin Support Group - Bereavement (General) | |
| Twins and Triplets | |
