International 9p Minus Awareness Day is observed worldwide every September 9 to educate the public about 9p deletion syndrome, a rare chromosomal disorder caused by the deletion or absence of DNA on the short arm of chromosome 9. This disorder, also known as monosomy 9p or Alfi’s syndrome, affects approximately one in 50,000 births and can lead to various symptoms, including craniofacial abnormalities and developmental delays. Participants are encouraged to learn about the condition, share knowledge, and donate to the Chromosome 9p Minus Network. Additionally, individuals may advocate for local authorities to illuminate significant buildings in blue and green to enhance public awareness. The day aims to promote further research and support for affected individuals and their families.