Electromagnetic spectrum (EMS) is considered as a scarce and hence valuable resource by organisations operating spectrum-dependant (SD) systems. In the military context, the ability to control access to electromagnetic spectrum is crucial in the modern battlefield where advanced systems compete for spectrum. A commander would not commit forces to an area in which he could not reasonably expect to contest freedom of action and the EMS is no different. Access to spectrum when and where required is essential for a number of current and future Defence capabilities during wartime and peacetime alike. Defence organisations own and operate a complex and advanced mix of SD systems in the C4ISR domain, including but not limited to, space and terrestrial communications, radars, telemetry, training aids, base protection, weapon control systems and electronic warfare systems. These applications are integrated to maritime, ground and air platforms. In this brief we will discuss the impact of increased competition between civilian and Defence systems for spectrum: challenges faced by Defence spectrum managers in terms of spectrum-sharing to meet the demand, decisions made at World Radio Conference 2019, spectrum pricing review and changes to spectrum landscape in Australia in the 2019/20 period.