Despite recognition of the importance of a developmentally appropriate approach to sexuality education, there is little direct guidance on how to do this. This study employed in-depth interviews with experienced sexuality educators and developers of sexuality education materials to identify how this concept is understood and applied in the field. Developmentally appropriate sexuality education was conceptualized consistently across interviews to include (a) addressing developmentally relevant topics, (b) adapting content to cognitive development, (c) accommodating developmental diversity, and (d) facilitating the internalization of sexual health messages. However, these views fell short of incorporating the breadth of knowledge offered by adolescent development research.