Retention of students in secondary schools is an important move as it gears towards the fulfilment of convections which advocates for Education For All (EFA). Many of the studies already conducted have examined the theories that relate to student departure/retention more than the role of institutions in students' retention. As such, the author sought to examine the administrative strategies employed by various school administrators to guarantee secondary school students' retention in Aldai Constituency. The study also sought to explore the challenges faced by school administrators in their application of administrative strategies to ensure students' retention. The study adopted a mixed methods research design. The target population comprised public secondary schools in Aldai Constituency, their respective administrators, classroom teachers and Form Three students. Secondary schools were selected using stratified random sampling technique. The basis of stratification was school type. School administrators were purposively sampled. Simple random sampling technique was employed in selecting the classroom teachers. Questionnaire, interview schedule and content analysis were the main instruments of data collection. Both qualitative and quantitative data were collected for the study. Qualitative data was analyzed descriptively by computing frequency counts, percentages and measures of central tendency. Multi-linear regression analysis was computed to establish the most ideal administrative strategy that could be employed to ensure maximum students' retention. The study established that school administrators employ free communication, provision of bursaries and grants, enhancement of school culture and raising of school motivation levels administrative strategies in ensuring students' retention. They, however, encounter social, school and home-based challenges in their administration. The study recommends that free and open-communication should be reinforced and applied by all school administrators since it ranked highest in influencing students' retention. The study also recommends that the government should increase budgetary allocation for school bursaries and grants to ensure that needy students from vulnerable backgrounds complete their education.