The 2nd World Congress on High Entropy Alloys (HEA 2021) is a cross-disciplinary technical forum designed to share the latest research advances in single-phase and multi-phase metallic, intermetallic, and ceramic high entropy materials for functional or structural applications. HEA 2021 will feature highly focused technical talks on topics that include, but are not limited to, fundamental theory of alloy design, computational modeling and simulation, properties, processing, and applications of high entropy alloys.