Guild of Natural Science Illustrators - Non-profit organization that sets professional standards, provides opportunities for professional and scholarly development, encourages and assists member networking. - http://www.gnsi.org/
The Illustrators' Partnership of America (IPA) - Non-profit organization dedicated to promoting the business of professional illustration and protecting the intellectual property rights of its members. - http://www.illustratorspartnership.org/
Israel Association of Illustrators - Non profit organizations for the advancement of the profession of illustration in Israel. Includes members portfolios. - http://www.illustrators.org.il/
The Association of Illustrators (AOI) - Non-profit trade association dedicated to its members’ professional interests and the promotion of illustration. Provides news, membership information, portfolios and events. - http://www.theaoi.com/
Society of Illustrators San Diego - Professional organization that promotes the interests of illustrators. Includes activities, resources, membership information, and samples of members' work. - http://www.societyofillustratorssandiego.org/
Association of Medical Illustrators (AMI) - International organization composed of medical illustrators, related professionals, and students. Membership information and member directory. - http://www.medical-illustrators.org/