This study examined the establishment of school counseling units and qualities in the selection/appointment of school counselors in public secondary schools in Tanzania. A multiple case study design of the qualitative research was employed in the inquiry process. The study involved nine heads of schools, forty-six teachers and forty-eight students purposively selected from nine public secondary schools in three regions. Data were gathered using focus group discussions and interviews and were analyzed thematically. The findings revealed that few schools had established fully-fledged counseling units and had selected school counselors by involving students. In other schools, the selection/appointment of school counselors was conducted or influenced by the Heads of Schools, contrasting the Education Circular guidelines, which require collaboration with the students. Teachers' personal traits, such as age and willingness to help, and professional qualities, such as counseling training and teachers' working experience, were considered in the selection of counselors. The study recommends Heads of Schools to establish counseling units in their schools and adhere to the stipulated guidelines in the selection of school counselors. Also, policy-makers in the education sector should consider formalizing the criteria preferred by Heads of Schools, teachers, and students in the selection of school counselors and include them in the existing guidelines for effective school counseling services.