The invention of Global Navigation Satellite Systems (GNSS) revolutionised the world and thoroughly transformed the maritime industry. This change has been a positive one overall, with safety and efficiency improved as a result. Like all technologies there are always trade-offs and the maritime industry has not been immune to challenges.In this article, Richard Bell, Assistant Director: Maritime Safety & PNT Services at the UK Maritime and Coastguard Agency, talks about GNSS vulnerabilities, Enhanced Long-Range Navigation System (E-Loran) as an alternative, and the steps ship owners/operators can adopt to strengthen their ability to withstand disruptions.While GNSS has proven a reliable tool, it is not a resilient one. Being a low power/high frequency system, GNSS is vulnerable to denial via jamming and spoofing, and the maritime industry has reported regular denial events at various locations around the world, often associated with conflict zones.Additionally, one of the unintended consequences of GNSS use in the last two decades has been the atrophy of traditional navigation skills among some deck officers. The ability to respond to GNSS denial events varies significantly between organisations and Deck Officers. This is exacerbated by a lack of awareness of the frailty of GNSS service in general. It could be argued that some elements of the maritime industry (organisations and personnel) moved too completely into the GNSS age. However, the UK recognises these risks and is implementing an alternative terrestrial PNT system, which will serve the UK and surrounding waters called E-Loran. E-Loran is independent of satellite infrastructure and while other technologies exist for navigation (DES R-Mode, Quantum, Inertial Navigation Systems), only E-Loran offers the maturity, capability and proven resilience required by the maritime industry at this time.Another benefit of E-Loran is that, as of now, multiple countries in different regions have independently created or ar