Diversity and the underrepresentation of women, African-Americans, Hispanics and American Indians in the nation's science, technology, engineering and mathematics (STEM) fields are the subjects of the XV: A View from the Gatekeepers--STEM Department Chairs at America's Top 200 Research Universities on Female and Underrepresented Minority Undergraduate STEM Students. Annual public opinion research project commissioned by Bayer Corporation, the Bayer Facts surveys examine science education and science literacy issues. The 15th in the series and the fifth to explore diversity and underrepresentation, this research is a direct outgrowth of last year's results which found 40 percent of the country's female and underrepresented minority (URM) chemists and chemical engineers working today were discouraged from pursuing their STEM career at some point in their lives. US colleges were cited as places where this discouragement most often happened and college professors as the individuals most likely responsible. Does such discouragement still occur in American colleges today? To answer this and other questions about the undergraduate environment in which today's students make their career decisions, the survey polls 413 STEM department chairs at the nation's 200 top research universities and those that produce the highest proportion of female and URM STEM graduates. The survey also asks the chairs about their institutions track record recruiting and retaining female and URM STEM undergraduates, preparedness of these students to study STEM, the impact of traditional introductory STEM courses on female and URM students and barriers these students face pursuing their STEM degrees.