This chapter shows how and why Australian firearm legislation altered very little for 65 years, but changed dramatically in 12 days. It explains the ‘perfect storm’ of horror, outrage, law and leadership which forced policy reversal, and details the lightning legislative adjustments now held up as global good practice. In addition, and with 20 years of research and hindsight, it describes the attitude adjustment which enabled effective enforcement of gun laws, and the notable improvements to public health and safety which followed, perhaps as a result.