In recent years, the protection of dark and quiet skies (D&QS) has become an increasingly urgent concern, driven by the proliferation of artificial light at night (ALAN) and the deployment of mega-constellation satellites in low-earth orbit (LEO). This paper presents preliminary research findings from the IAU CPS Policy Hub National Analysis Team, focusing on the national policy and legal approaches to safeguarding D&QS for astronomical observations worldwide. It synthesises the key interim results with a primary focus on light pollution mitigation, outlining measures to combat light pollution and emerging regulatory trends. The study also identifies obstacles to mitigating light pollution and offers examples of national approaches for D&QS protection, along with future research prospects.