[en] Under the auspices of the NEA Nuclear Science Committee (NSC), the Working Party on Scientific Issues of Reactor Systems (WPRS) has been established to study the reactor physics, fuel performance, radiation transport and shielding, and the uncertainties associated with modelling of these phenomena in present and future nuclear power systems. The WPRS has different expert groups to cover a wide range of scientific issues in these fields. The Expert Group on Radiation Transport and Shielding (EGRTS) was created in 2011 to perform specific tasks associated with radiation transport and shielding aspects of present and future nuclear systems and accelerator-based irradiation facilities. The EGRTS provides expert advice to the WPRS and the nuclear/accelerator communities on the development needs (data and methods, models and codes, validation experiments) for various nuclear and accelerator systems and scenarios and also provides specific technical information regarding : - 3D radiation transport codes and methods; - Pressure vessel surveillance; - Shielding and dosimetry aspects of accelerator, target and irradiation facilities; - Neutron activation and shielding. This report aims to compare the results of advanced three-dimensional transport methods and codes to high quality reference solutions