DACCORD-1: This decommissioning project provides representative input and benchmarking data required for the costing of research reactor decommissioning at preliminary planning stages. These data are important for plant managers and policy makers involved in decisions on how to proceed with decommissioning. The final cost for decommissioning can vary considerably on account of the large number of different types of research reactor, construction complexity, different planned end states, events during operation that affect decommissioning, and differing capabilities concerning spent fuel and radioactive waste management. Three main working groups undertook this work and addressed TRIGA research reactors, pool-in-tank research reactors and open pool research reactors.