The wasteforms used for high-level nuclear waste immobilisation are required to remain stable despite prolonged exposure to self-irradiation from the waste elements contained within the matrix, as well as to groundwater, to ensure they can be safely isolated in the geosphere over geological timescales. This PhD project has addressed these challenges by examining the synthesis of these waste forms, as well as the radiation tolerance and aqueous durability of several candidate and surrogate nuclear waste forms for emplacement within a geological disposal facility. Four different wasteforms were chosen for this study: International Simple Glass 2 (ISG-2, a model borosilicate glass), a Ca/Zn-based glass-ceramic, and finally two titanate ceramics: perovskite and zirconolite. Three main research objectives were established for this work. First, the project would synthesise non-active surrogates of the two titanate ceramics used in this work - zirconolite and perovskite - with the objective of optimising sintering parameters to improve the microstructural characteristics and phase purities of the materials. Second, corrosion studies would be performed of the synthesised zirconolite and perovskite materials using different corrosion durations, temperatures and pH regimes to assess their aqueous durability. Third, all four materials would be ion-irradiated to simulate the impacts of long-term radioactive decay within these materials (self-irradiation damage), followed by post-irradiation corrosion tests to assess the impact of radiation damage on corrosion. By combining synthesis, irradiation, and corrosion work, the project yielded new insights into the coupling relationship between irradiation damage and aqueous corrosion in nuclear wasteforms. These findings will contribute to the design of nuclear high-level waste packages designated for deep geological disposal, thereby enhancing the long-term containment of radioactive waste for millennia to come.