The Law of the People’s Republic of China on Safeguarding National Security in the Hong Kong SAR (the National Security Law or “NSL”) promises to be the most important legal development in Hong Kong since the advent of the Basic Law. In the aftermath of the NSL, many wondered how the foundations of Hong Kong’s system might be changed and in what way the freedoms valued by Hong Kong might be affected. Supporters view the law as essential for the preservation of public order and the national security of China, as well as supporting the fundamental well-being of “One Country, Two Systems,” an arrangement that has been in place since the return of Hong Kong to China, while critics fear an adverse impact on the spirit of “One Country, Two Systems.” This collection of essays brings together leading experts on Hong Kong and Chinese law to offer an exploratory study of the NSL and its impact on the legal system and the principle of the rule of law in Hong Kong.