The Federation of Clinical Immunology Societies (FOCIS) was initially established as a cross-disciplinary meeting, holding its first Annual Meeting in 2001. It subsequently became a 501(c)3 organization in 2003. Its mission is to improve human health through immunology by fostering interdisciplinary approaches to both understand and treat immune-based diseases. FOCIS currently has 53 Member Societies, representing roughly 65,000 clinician scientists.