Challenges related to extended storage are topical in most countries with mature nuclear programmes. Effort to address this issue is ongoing in individual countries. Available knowledge from member countries was gathered and appraised to identify and assess the impact of technical, safety and regulatory, economic and social factors related to different storage options, fuel types and technical conditions. Strategies to manage waste, i.e. managing the time and phasing of decisions to ensure that the best decisions are made at the right time, were analysed in this context. The main output of the expert group was a state-of-the-art report.