This study is situated within a large-scale national high school level engineering education initiative that aims to "demystify" engineering for high school students, teachers, and counselors through an all-inclusive high school level engineering course. Counselors participated in a series of PD activities centered on the following components: (1) design and development of a new engineering course open to all high school students, (2) teacher and counselor PD, and (3) a learning community of teachers, counselors, engineering educators, and practicing engineers. We utilized an exploratory qualitative research design to understand counselors' perceptions and experiences. Through their own hands-on experiences, counselors had concrete examples to share with students about engineering as a field to consider for postsecondary education and careers. Further, through a broadened understanding of the skills needed to excel in engineering, counselors expressed that they would work with all students to recommend them towards engineering, rather than just the "math and science" students. Through this study, we identified an important gap in the engineering pipeline: high school guidance counselors. In order to broaden participation in engineering, we must first expand the knowledge of those people working closely with high school students on postsecondary plans.