Within cross-curricular literacy (CCL) initiatives at colleges and universities, there still remain challenges in preparing and supporting instructors from different disciplinary backgrounds. This small, exploratory study investigates the ways that literacy experiences and disciplinary backgrounds shape the teaching practice of five science writing instructors, three with English/Writing Studies backgrounds, and two with science backgrounds. Findings show that, for instructors in our discipline-linked program, disciplinary background shapes their course goals, their need for cross-disciplinary mentoring, and their levels of confidence in teaching science writing. Reflections for CCL leaders conclude the article.