This proposal "Mucosal Immunity: A Trudeau Institute Workshop" requests funds to support a workshop entitled "Mucosal Immunity: Creating a balance between barrier and function at the mucosal frontier" hosted by the Trudeau Institute. The meeting will be held October 9-11, 2009 at the Trudeau Institute. The current workshop will gather approximately 65-70 investigators in an informal setting to discuss current topics related to the mucosal immune response. The goal is to identify, review and discuss the most important unanswered questions in the field. The format of this meeting will be a series of 5-10 minute talks organized around key questions, with the emphasis placed on discussion and interaction rather than formal presentations. Participants are given the opportunity to suggest topics for discussion and to present data in any session(s) of their choice. Participation is by invitation only. The organizing committee selected possible participants based on their contributions to the field of mucosal immunity or to related fields, such as vaccination, immune response to allergy, commensal biology, infectious disease or autoimmunity. By necessity, we have primarily selected senior investigators who have both the breadth and depth of experience to contribute to multiple sessions in the workshop. In addition, we have also selected scientists who are in the early stages of their careers, but based on their training and their recent contributions to the field of mucosal immunity, are likely to be prominent in the field. This proposal requests funds to support travel, accommodation and meals for five of these relatively junior investigators. Since the choice of participant was based on their long-term contributions to the field of Mucosal Immunity, the majority of invitees are senior investigators and, as such, they are representative of senior investigators in immunology in general. As reported by the Chronicle of Higher Education 2004 51(15) pA8, women make up 15% of the Full Professors and 31% or the Associate Professors at research institutions. Since 20% of the invited speakers, 29% of our SAB, 44% of our faculty and 25% of our trainees are women, we feel that we have successfully included women in the workshop program. In addition, 2 of the 4 workshop organizers are women and 2 of the 5 early-career investigators for whom we are requesting support are women. According to The Scientist 2004 18(22) 43-45, the population of life scientists is composed of 16% Asian and Pacific Islanders, 0.3% Native Americans, 3% Hispanics and 2% African Americans. These statistics include scientists at all levels and we expect that minorities will be even less represented at the senior levels. We have included a question in our invitation letter but have not yet received sufficient responses to make a self- identified statement regarding ethnicity however, in our choice of invitees we have, apparently, 11% Asian and 2% African American, the rest being white. Finally, the Trudeau Institute has facilities to accommodate anyone who is physically disabled. The organizers are Andrea Cooper, Markus Mohrs, Yasmine Belkaid and Bali Pulendran.