The main objective of the study was to assess the implementation of SIP in West Arsi Zone rnSecondary Schools. Descriptive research method was used. Data for this study were collected rnfrom Teachers, principals, supervisors, student councils and PTA members. Stratified, simple rnrandom and availability sampling techniques were employed to select the sample respondents. rnTo this effect, 150 teacher participants were selected using stratified and simple random rnsampling techniques. Besides, 5 principals, 5 supervisors, 5 studentsâ€™ council members and 5 rnPTA members were selected by availability sampling technique method. Questionnaires andrninterviews were used as instruments for data collection. And, the collected data were analyzed rnusing both quantitative and qualitative methods. The results of the study showed that the schools rnwere not as such frequently evaluated and discussed with teachers on the program planning and rnimplementation outcomes, the involvement of parents in preparation of school improvement rnprogram was low, stakeholdersâ€™ involvement in self-evaluation was not satisfactory, SIP was not rnwell communicated to school community (teachers, students and parents), the school rnimprovement committee has not contributed in coordinating, monitoring and evaluating the rnimplementation of school improvement program, there was also low team work among rnstakeholders to implement the SIP, parents involvement in preparation of SIP was unsatisfactory, rnprincipalsâ€™ engagement in improving learning conditions and learning outcomes was low and rnparents and community involvement in the school affairs was low.