To rapidly communicate short reports of innovative responses to Covid-19 around the world, along with a range of current thinking on policy and strategy relevant to the pandemic, the Journal has initiated the Covid-19 Notes series. Facing the coronavirus pandemic, Australia has achieved national consensus on policies that were unprecedented for the past century. New South Wales (which has 8 million residents) and other jurisdictions appear to have successfully suppressed Covid-19 transmission after a rapid escalation of cases in March 2020. The first four cases, all linked to the Wuhan outbreak, were identified in Sydney in late January. The New South Wales Ministry of Health (NSW Health) followed its new Covid-19 protocols to isolate infected people and quarantine their contacts. No transmission resulting from these cases was detected. The Australian government restricted entry for travelers from China on February 1. No further cases were identified in New South Wales until late February, when several travelers from Iran and their contacts tested positive. As Covid-19 continued its international spread, people who had traveled overseas, particularly those returning from the United States and Western Europe, accounted for most Australian cases. In late March, there was another upswing in new cases, this time resulting from infections acquired on cruise ships. Images from Europe of coffins and overflowing intensive care units made things look grim. The New South Wales government’s response built on previous pandemic planning that was informed by lessons from severe acute respiratory syndrome (SARS) and H1N1 influenza. On January 21, NSW Health opened its Public Health Emergency Operations Centre (which was previously used during the H1N1 influenza pandemic and for subsequent exercises) to coordinate case finding, contact tracing, outbreak control, communications, and other preventive actions. It drew staff from health services, government agencies, universities, and former employees. More than 150 contact tracers were hired, and the State Health Emergency Operations Centre was opened at the Rural Fire Services headquarters to help the state’s 17 local health districts build critical care and emergency department capacity, establish Covid-19 testing clinics, and coordinate the supply of personal protective equipment. NSW Health regularly produced online content and webinars for physicians, health administrators, and other stakeholders. Expert committees, led by the Communicable Disease Network Australia and its parent organization, the Australian Health Protection Principle Committee (AHPPC) — both of which include jurisdictional health department staff and academic experts — meet daily to review surveillance data and models of projected disease spread and to develop recommendations. The AHPPC advises the newly formed national cabinet (composed of the prime minister and the first minister from each state and territory), which then creates policies, recommends legislation, and implements laws related to Covid-19. Since February 1, the Australian government has increasingly tightened its border-control policies, and by March 15 it restricted entry for all foreigners. Mandatory 14-day quarantine in hotels for residents returning from overseas, closing of borders between some jurisdictions, and bans on gatherings and nonessential travel, all of which are enforced by police, followed. Most office work and studying is now done from home, and food outlets are restricted to offering take-away services. Anzac Day ceremonies to commemorate defense personnel on April 25 were cancelled in favor of private remembrance. To identify as many cases as possible and thereby avert further disease transmission, special attention has been given to increasing testing capacity and broadening access to testing for people with mild symptoms. New South Wales now has among the highest testing rates in the world. To strengthen traditional contact-tracing methods, the Australian government launched COVIDSafe, a mobile app that uses Bluetooth to identify close contacts of people with Covid-19, on April 26. Like the rest of Australia, New South Wales is currently in a lull — new diagnoses have fallen from a peak of 212 on March 27 to 1 on May 3. This success may be attributable to Australia’s near-unique ability to close its borders as well as to consistent national Covid-19 policies, regular communication with an engaged community, effective identification and isolation of infected people, quarantine of those who have been exposed, and the public’s high degree of compliance with social-distancing guidelines. Without high rates of population immunity, New South Wales remains susceptible to Covid-19. We might be winning the battle, but the social and economic costs are high. The question now is whether robust identification of new cases and contact tracing can limit transmission sufficiently to permit relaxation of some social measures before a vaccine is available.