Welcome to Meeting Professionals International Washington State Chapter (MPIWSC) Please install Flash® and turn on Javascript to view the Photo Gallery Meeting Professionals International, the world’s largest association for the $102.3 billion meeting and event industry, is committed to positioning meetings and events as a key strategic component of an organization's success. The 350 member Washington State Chapter, established in 1981 empowers its members to increase their strategic value with education, professional development and business growth opportunities.