In this episode we are talking about PNT – that’s Positioning, Navigation, and Timing – systems, their use within many aspects of critical national infrastructure, and their extensive impact on our daily lives. We are joined by Professor Washington Ochieng, Head of the Department of Civil and Environmental Engineering, as well as Chair in Positioning and Navigation Systems at Imperial College London. He is also the Senior Security Science Fellow at the Institute for Security Science and Technology at Imperial. With a background in industry and academia, Professor Washington Ochieng has participated in various international industrial programmes developing satellite navigation systems, and has undertaken award-winning research in critical infrastructure resilience and PNT systems. The Zero Pressure podcast series looks at how science and technology positively can contribute to solving complex, interrelated global challenges of today and tomorrow. We look at pioneering technologies and speak to those on the thinking edge. Zero Pressure is a podcast from Imperial College London and Saab. A relaxed conversation with those on the cutting edge of science and technology - hosted by Britain's first astronaut Helen Sharman - Presented by Imperial College London and Saab.