In this supplement on ‘Marxism and renewal in the 21st Century, we explore new sources of Marxism in an effort to enhance theoretical analysis. This may serve as a basis for shaping new anti-capitalist politics and envisioning alternatives (such as ecosocialism, solidarity economy and feminism). The following articles take stock of Marxism today and interrogate its potential for navigating alternatives in the future. The authors span a wide range of issues and perspectives, all having to do in some way with Marxism. One of the main themes is Marxism and Global capitalism where Burawoy reperiodises Marxism along three waves of commodification and Satgas explores the globalising of Gramscian Marxism. Another is Marxism and Anti-capitalism, discussed by Pillay in an article on Eco-Marxism, Jacklyn Cock on Feminism and Van der Walt on Anarchism’s engagement with Marxism. Although John Saul did not appear at the conference, his views on the working class as an agent of change is relevant to this supplement. His article and that of Daryl Glaser on Marxism and Africa are the Marxism and Socialism section. The authors raise concrete questions about contemporary forms of activism and explore emerging themes around which to organise, such as ecological issues, forms of production (cooperatives), green–red alliances, etc.