The Sam Day Foundation advocates for children battling cancer, focusing on funding research and wellness initiatives for pediatric cancers, particularly Ewing Sarcoma and other forgotten cancers.

The United Brachial Plexus Network supports individuals and families affected by brachial plexus injuries by providing information, resources, and connections to care providers.

The San Diego Regional Center provides support and services to persons with developmental disabilities and their families, helping them achieve their goals and maximize their independence.

The Sanfilippo Children's Foundation supports research for Sanfilippo Syndrome, a rare genetic condition causing fatal brain damage in children, and funds projects aimed at finding treatments and a cure.

La Fondation Sanfilippo Suisse œuvre pour accélérer la découverte d’un traitement contre la maladie de Sanfilippo, une maladie dégénérative rare, et fournit un soutien aux enfants atteints et à leurs familles.

The Sarcoma Alliance provides support, education, and resources for individuals affected by sarcoma, helping them navigate their journey through diagnosis and treatment.

SARC is a non-profit organization focused on sarcoma research, providing resources and support to connect patients with expert care and facilitating clinical trials.

Save Babies Through Screening, Inc. is a nonprofit organization focused on ensuring that every newborn in the U.S. receives comprehensive screening for various diseases, providing education to parents and healthcare professionals about the importance of early detection and treatment.

The Scarring Alopecia Foundation is dedicated to advancing research, supporting patients, and providing education for scarring alopecia.

The Schinzel-Giedion Syndrome Foundation provides support to families caring for children with Schinzel-Giedion Syndrome, raises awareness, and facilitates medical research.

The organization supports individuals living with early psychosis and schizophrenia by promoting access to treatment, community support services, and research related to these conditions.

The Scleroderma Research Foundation is dedicated to funding and facilitating research aimed at improving therapies and finding a cure for scleroderma, a rare autoimmune disease.

The Selective Mutism Association provides comprehensive information and resources about selective mutism, an anxiety disorder, and offers support for families, educators, and professionals involved with affected individuals.

This organization supports Jewish communities by responding to crises, caring for vulnerable individuals, and strengthening Jewish identity and community.

SIECUS advocates for comprehensive sex education and promotes policies that ensure sexual and reproductive health equity for all individuals.

The Shaken Baby Alliance provides support, prevention, and justice for victims of child and elderly abuse, focusing on education and resources for families and professionals.

Share Pregnancy & Infant Loss Support, Inc. provides support and resources for families experiencing the loss of a baby through pregnancy loss, stillbirth, or in the first few months of life.

Shine is the UK’s leading charity supporting people affected by spina bifida and hydrocephalus, providing services such as helplines, support services, and health advice.