Polymers are among the most important mass-produced materials on the planet, yet they are largely derived from a finite supply of petrochemicals. To ensure the sustainable production of polymers and functional materials, alternative feedstocks are required. This Perspective examines this challenge in the context of an emerging class of polymers made from elemental sulfur. Because sulfur is a by-product of the petroleum industry, converting it into useful polymers and related materials is an advance in waste valorisation. Additionally, co-polymerisation of sulfur with renewable monomers represents an additional contribution to sustainability. These reactions are often solvent free and benefit from full atom economy, futher augmenting their Green Chemistry credentials. Applications of these materials will be discussed, with a spotlight on environmental benefits. A forward looking assessment of the opportunities for using sulfur polymers in Green Chemistry is also included.