NIH hosted a Twitter chat on rare diseases on February 22, 2016. NIAMS provided information on rare diseases that fall within the Institute’s mission, including autoinflammatory diseases, vasculitis, osteogenesis imperfecta and epidermolysis bullosa. NIH Director Francis Collins, M.D., Ph.D., participated in the chat, which reached over 1.5 million Twitter users. NIAMS tweets made over 65,000 impressions. Tweets from the chat can be viewed by searching on Twitter for #NIHChat and scrolling down to the tweets for February 22, 2016.