Microscopic plankton are essential components of aquatic food chains and food webs. They are amongst the most abundant organisms on the planet, yet many people underestimate the environmental impact of plankton destruction. In this podcast, I aim to shed some light on the key roles that phytoplankton and zooplankton play in ecosystems, and in doing so, hope to answer the question - why should we care? (With thanks to our sponsor 'Curriculum Press' for providing content for this podcast)