Around the world, leftists and progressives are making important electoral gains. New Zealand, the Iberian Peninsula and the Nordic countries lead the way, while the Democratic party candidate is hoping to regain the White House in the United States but first must bridge internal divisions. In other parts of the world, the centre-left is struggling to gain traction or unify around common ground, making it a daunting challenge to form new and stable alliances. The increased importance of climate change, different forms of identity, digitalisation and the just transition have changed the composition, priorities and tactics of left politics, and raises the possibility of new alliances to bring about progressive change.