College science instructors need continuous professional development (PD) to meet the call to evidence-based practice. New PD efforts need to focus on the nuanced blend of factors that influence instructors' teaching practices. We used persona methodology to describe the diversity among instructors who were participating in a long-term PD initiative. Persona methodology originates from ethnography. It takes data from product users and compiles those data in the form of fictional characters. Personas facilitate user-centered design. We identified four personas among our participants: Emma the Expert views herself as the subject-matter expert in the classroom and values her hard-earned excellence in lecturing. Ray the Relater relates to students and focuses on their points of view about innovative pedagogies. Carmen the Coach coaches her students by setting goals for them and helping them develop skill in scientific practices. Beth the Burdened owns the responsibility for her students' learning and feels overwhelmed that students still struggle despite her use of evidence-based practice. Each persona needs unique PD. We suggest ways that PD facilitators can use our personas as a reflection tool to determine how to approach the learners in their PD. We also suggest further avenues of research on learner-centered PD.