The Tourette Association of America (TAA) is dedicated to raising awareness, advancing research, and providing support to individuals and families affected by Tourette Syndrome and Tic Disorders.

Tourette Canada is dedicated to improving the lives of Canadians affected by Tourette Syndrome and associated conditions through education, advocacy, and community outreach.

TOFS is a charity that offers lifelong support for individuals born with Oesophageal Atresia (OA) and Tracheoesophageal Fistula (TOF), providing information for parents, carers, and healthcare professionals.

TRIO Transplant Recipients International Organization connects the pre and post transplant community, empowering patients and their families facing the need for an organ transplant and living life afterwards.

Triage Cancer provides free education on the legal and practical issues that arise after a cancer diagnosis, offering resources, events, and materials to support individuals affected by cancer.

The TRPM3 Foundation focuses on empowering individuals affected by TRPM3-related disorders through research, advocacy, and community support.

The TSC Alliance is dedicated to improving the quality of life for individuals affected by tuberous sclerosis complex (TSC) through research, advocacy, and support services.

The Tuberous Sclerosis Association supports individuals and families affected by Tuberous Sclerosis Complex (TSC) through dedicated advisers and community engagement.

The Turner Syndrome Foundation is a non-profit organization that provides advocacy, education, and support for individuals affected by Turner syndrome, facilitating research initiatives and enhancing medical care.

This organization focuses on raising awareness and providing support for Turner Syndrome, a genetic condition affecting females that can impact physical development and reproductive health.

The Turner Syndrome Society of the United States provides support and resources for individuals with Turner syndrome, including educational materials, community connections, and advocacy for telehealth access.

The Turner Syndrome Support Society provides support and information for women and girls with Turner Syndrome, focusing on their unique needs and offering resources such as publications, events, and advice.

The TTTS Foundation is dedicated to providing educational, emotional, and financial support to families affected by Twin to Twin Transfusion Syndrome (TTTS) and its related conditions, including TAPS, SIUGR, and TRAP.

The Tyrosinemia Society provides information and support for individuals affected by Tyrosinemia, including resources for patients, parents, and healthcare providers.

The UCSF Edward and Pearl Fein Memory and Aging Center provides expert diagnosis and care for individuals with memory and thinking issues, focusing on conditions like dementia and Alzheimer's disease.

This organization provides educational resources about cancer immunotherapy, including information on available treatments and the immune system's role in cancer.

The UDNF supports families with undiagnosed or ultra-rare conditions by providing resources for diagnosis, research, treatment, and community support.

United Cerebral Palsy advocates for people with disabilities, providing resources, education, and support to promote inclusion and independence.

The United Leukodystrophy Foundation (ULF) is a non-profit organization dedicated to supporting the leukodystrophy community by providing disease information, medical referrals, and funding research to improve patient quality of life.