This chapter examines security and Australian foreign policy during 2016–2020 using two strands. It shows that Australia confronted both the ‘high politics’ issues that are the stuff of traditional foreign policy, as well as the unconventional security challenges to which Australia had to adapt. We begin by considering Australia’s conventional security politics, and the three consistent strands in Australia’s security thinking: how Australia fits into a world of super powers and the balancing act it must conduct to do so; relatedly, its alliance with the Unitd States; and Australia’s role in multilateral organisations. We then assess the so-called ‘unconventional’ security issues and their impact on Australian national security. Our analysis reveals that Australia’s responses to unconventional threats were increasingly conventional and relied on domestic tools to solve international problems. Some new threats seemed to bring international tools, like the military, to bear on domestic problems. Moreover, we demonstrate that the security environment was increasingly defined by the ‘grey zone’ – acts that reside between war and peace and take on unconventional forms.