The Attraction-Selection-Attrition (ASA) model is a prominent framework for supporting employee retention, stating that organisations attract, select, and retain people who share their values. However, the ASA model only extends to the end of the recruitment stage and lacks clarity on how to assist newcomers in the assimilation process when they first join the organisation. This research proposed a refinement of the ASA paradigm by incorporating the assimilation process of new hires into the new school culture and environment. This study employed a qualitative research approach by interviewing ten participants about the retention process from high teacher retention international schools in Malaysia. Thematic data analysis revealed a new paradigm, 'Attraction-Selection-Onboarding-Retention (ASOR), ' designed to increase teacher retention in international schools. The ASOR model could assist school administrators and human resource managers working in a related setting in properly engaging the workforce to increase teacher retention. This would benefit school sustainability, performance and the local community's economy.