From 2016 to 2020 Australia put in place new legislation to counter perceived threats to Australia’s security, including the National Security (Espionage and Foreign Interference) Act 2018 (Cth) (‘Foreign Interference Act’), Foreign Influence Transparency Scheme Act 2018 (Cth) (‘FITS’) and Australia’s Foreign Relations (State and Territory Arrangements) Act 2020 (Cth) (‘Foreign Relations Act’). These domestic laws, which are enforced by the police and other security agencies, were presented as a response to foreign interference in Australian politics and democracy, especially by the People’s Republic of China. During the same period, Australia’s relationship with China deteriorated markedly, including a freeze on high-level contacts and trade retaliation. This chapter focuses on the impact of these new domestic laws on Australia’s international relations and assesses whether they were a significant factor in the worsening of Australia–China relations during this period.