International MPS Awareness Day is observed worldwide every May 15 to honor patients affected by mucopolysaccharidoses (MPS) and their caregivers. Established in the United States in 2006, this awareness day is coordinated by the National MPS Society and the International MPS Network, which connects MPS organizations globally. The day aims to improve awareness of MPS, a group of over 40 rare genetic disorders caused by the deficiency of enzymes that break down glycosaminoglycans (GAGs). Activities on this day include participating in local or virtual events, sharing information about MPS, and supporting charities that assist MPS patients and their families. People are encouraged to use social media hashtags like #InternationalMPSAwarenessDay and #MPSAwarenessDay to spread the message.