Underwater robots are increasingly utilised for commercial and scientific applications to make measurements and interact with the underwater environment. The A2I2 (Autonomous Aquatic Inspection and Intervention) robots will operate in hazardous underwater environments, for offshore renewables, oil and gas, and nuclear applications. Two specific intervention use-cases will be addressed through demonstrators; offshore coring, and wet nuclear storage pond inspections and interactions. These demonstrators are significantly different and therefore enable the project to address multiple market opportunities. This project will address the need for new approaches that are required to permit operation near to critical infrastructure. These will include increased intelligence on the underwater robots to enable them to position themselves and navigate avoiding collision with the surrounding environment.