The assessment of isolators as barrier technology in the context of Annex 1 depends on various factors, including manufacturing methods, product characteristics and specific process and transfer risks. The choice of a barrier technology is a crucial step for pharmaceutical manufacturers to ensure the highest quality standards. Isolators, as established barrier technology provide a physical separation between the manufacturing process and the external environment. As a closed system, they enable full control over the process held therein, which is particularly important in the production of sterile drugs. Isolators can efficiently integrate multiple manufacturing steps and provide a flexible platform for complex production processes.