The use of science, technology, engineering, and mathematics (STEM) mentors in public school systems and other organizations has grown comparably with our economy's increasing demand for STEM industry professionals. However, inspiring students to pursue STEM careers by using STEM industry professionals as mentors requires an understanding of effective mentor practices. Limited research exists that focuses on the mentoring practices students respond to as they make academic and career plans. The purpose of this study was to investigate and identify practices that promote STEM careers among youth. The study sought to answer the question, "What STEM mentor practices, behaviors, and roles do students identify as increasing their interest in pursuing STEM careers?" This study used a qualitative case study methodology. Golden Meadows School District was selected due to its extensive secondary education STEM mentoring programming. STEM education courses and activities are offered district-wide at the Center for STEM Instruction and Innovation (CSII). Golden Meadows was also chosen for the longevity of its program and the variety of STEM-focused project teams. The project teams were supported by industry mentors recruited from local businesses. The study focused on the perspectives of mentees working with industry mentors from various STEM disciplines. Students in the 11th and 12th grades were asked to participate in interviews. Participants answered questions about mentoring experiences that influenced their plans to pursue STEM professions. Interview responses and project team artifact review were used to analyze mentee perspectives. Two themes emerged from the findings which defined practices identified by mentees. The findings revealed that mentees pursuit of STEM careers was influenced by mentor practices that built mentee self-confidence and a comprehensive understanding of STEM careers. The study is supported by previous research focused on the value of mentoring and its use to positively influence young people. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]