Most graduate students and new faculty have little, if any, preparation for teaching the approximately 40% of college composition students who are 25 years or older. Thus, it falls to WPAs to prepare new teachers to work with adult students. To assist WPAs, this article addresses common misconceptions about adult students, reviews scholarship on the differences between older and younger students as well as between different populations of adult students, and discusses ways to leverage the strengths and address the needs of adult students. The “Teaching Writing to Adults: A Handbook for New Composition Teachers” on CompFAQs supplements this article with sample assignments, recommended readings, cases for discussion and other support for those new to teaching adult students.