In his classic 1818 sonnet on the remains of a huge statue of an Egyptian pharaoh, Percy Shelly wrote, "My name is Ozymandias, king of kings: Look on my works, ye Mighty, and despair!" The boasts of the king, over time, have been reduced to ruin and desert. This reflects the decline of many past civilisations and may provide warnings for our own societies. In a 2014 study part-funded by NASA's Goddard Space Flight Centre, natural and social scientists developed a model predicting how a combination of unsustainable resource exploitation and increasingly unequal wealth distribution could lead to the implosion of global civilisation within decades. Things aren't necessarily looking good. In this lecture, we will explore the rise and collapse of societies such as those responsible for the Easter Island statues and the pyramids of Maya. Many populations have imploded from self-inflicted environmental catastrophes, others from circumstances seemingly beyond their control. We will describe the decline of the Vikings and the effects of trade on the Pitcairn Island group, together with the problems facing modern societies, from the genocide in Rwanda to the large-scale mining projects in Australia. To conclude, we ask why so many societies appear to make self-destructive decisions and the likely effects of resource extraction and climate change on our own civilisation.