This study aimed to develop and validate the ASCA-Informed Student Needs Assessment--High School Version, an ASCA-informed and practitioner-friendly instrument that high school counselors can administer to students to identify pressing student needs. The results revealed a four-factor model consisting of the following dimensions: (a) school connectedness and prosocial skills, (b) social/emotional support, (c) academic and career development, and (d) relationships and emotional regulation. The study's findings suggest suitable reliability and validity. This article discusses implications and areas for future research.