Climate change poses significant financial and ethical challenges for shareholders, who must decide whether to continue to invest in fossil fuel companies, and/or how they will engage with the firms in which they remain invested. Investors are also coming to recognise the financial risks to their investment portfolios stemming from decarbonisation of the global economy. We discuss these risks below. Fossil fuel divestment and shareholder engagement have both been put forward as appropriate models for responding to this challenge. In this briefing we set out the implications of the Paris Agreement for fossil fuel extraction and for investors in fossil fuels. We explore the origins and progress of the divestment movement and set out divestment principles.