Gamma-ray diagnostics at JET (gamma-ray spectrometry and imaging) have provided some of the most interesting results in experiments such as those of the TTE campaign. The extension of the application of this diagnostics to high power deuterium and, especially, deuterium­tritium discharges is however limited by the present capabilities of these diagnostics. For instance, with the existing diagnostics capabilities the gamma-ray signal is completely overwhelmed by neutron events even in JET discharges using a few MW's of neutral beams. A coherent set of upgrades was therefore considered indispensable to extend the JET gamma-ray diagnostic capabilities and to improve the measurements in order to better support the experimental programme. In this respect, within the GRC EP2 Enhancement project the matter of the operation of the gamma-ray detectors in intense neutron and gamma-ray fields was addressed for two of the JET gamma-ray diagnostics: ­ The KN3 Gamma-Ray Cameras ­ The KM6T Tangential Gamma-Ray Spectrometer Design solutions based on water neutron attenuators have been developed for the KN3 Gamma-Ray Cameras (the KN3-NA diagnostics upgrade). A conceptual design was produced for the full line-of-sight of the KM6T Tangential Gamma-Ray Spectrometer, with the main design target being the maximisation of the "signal to background ratio" at the spectrometer detector, the ratio being defined in terms of the plasma emitted gamma radiation and the gamma-ray background.