Research provides considerable evidence that students of effective teachers have significantly higher achievement than students of ineffective teachers. According to the research findings, the induction support provided to beginning teachers who are less effective can accelerate their professional growth, making them more effective faster. Although there is no universal best practice in beginning teacher induction, there are many programs around the world that are well-planned and executed. When designing beginning teacher induction programs, it is wise to take into consideration the policies and practices that proved successful. With this aim, this study adopted a cross-national comparative case study approach to investigate the new teacher induction program of the USA (State of Wisconsin Sample), one of the earliest implementers of national teacher induction scheme (1992), and that of Turkey, who has been implementing a systematic teacher induction since 2016, in detail to help in reviewing and strengthening the induction policies and practices of Turkey. Accordingly, qualitative data were collected through document analysis and semi-structured interviews with program directors, beginning teachers and mentors in each country and subject to both within and cross-case analyses to identify the similarities and differences across the cases and determine the best practices. Finally, some policy suggestions were made, such as employing full-time high-quality mentors using a precise mentor selection process based on qualities of an effective mentor, offering mentors initial and continuous professional development opportunities, providing sanctioned time for mentor-teacher interactions, describing the roles and responsibilities of all program stakeholders clearly and promoting cooperation among all stakeholders. The study expects to provide information to policy-makers and leaders in an effort to provide a precise analysis of the teacher induction program in Turkey and to suggest areas where we can learn from another implementation.