Different types of glass-ceramic composites are being researched around the world as potential matrices for nuclear waste conditioning. To demonstrate their long-term durability and build a safety case for geological disposal, accelerated irradiation tests simulating He accumulation and the effects of recoil nucleus damage are needed. To study the behaviour of He in these materials, particularly, in zirconolite-based glass-ceramics, transmission electron microscopy (TEM) with in-situ ion irradiation was employed. This research work provides a detailed overview of the various parameters such as the implantation temperature, He concentration, structural disorder, grain boundaries, glass-ceramic interfaces, ballistic collisions etc on He accumulation and bubble formation in these materials. These results are then discussed in the context of nuclear waste disposal in ceramics and glass-ceramic-matrix based materials.