‘ECMetAC Euroschool 2021: Complex Intermetallic Compounds for Applications’ will be held online on 24-28 May 2021. This is an annual event (15th in series) organised by the European Integrated Centre for the Development of New Metallic Alloys and Compounds (ECMetAC). The school will focus on potential applications of complex intermetallic in various areas. It will offer lectures by experts in the field revising progress to date and prospect ahead, and tutorials/hands-on trainings. The target audience of the event is Ph.D. students, doctorate fellows, and people new to the field of material science and physics. Young researchers will have an opportunity to establish a network among them.