A disciplinary literacy framework suggests that content-area teachers are best positioned to guide students into discipline-specific ways of reading, writing, and communicating, such as teaching science students to write as scientists do. "Disciplinary literacy instruction" can move students beyond generic literacy strategies and prepare them better for further learning--but most principals are not deeply versed in all content areas. The authors give specific suggestions for how principals can encourage teachers to use disciplinary literacy instructional strategies and keep guiding them to do so.