Innovative and flexible supply solutions are critical success factors in a market that is constantly evolving with the liberalisation of European gas markets, unbundling of the once integrated gas and utility companies and a shift in customers' demand patterns. Market participants are adjusting their procurement strategies to the new market conditions, thus facing the need to actively manage their portfolio in order to ultimately benefit from new market opportunities. E.ON D-Gas Storage a subsidiary of E.ON D-Gas, therefore offers Rapid Response Flexibility Services available via Oude Statenzijl on the Dutch/German border with as delivery point the TTF. These services give energy market participants the ability to meet the needs of hourly flexibility in the gas markets. The Flexibility Services are asset backed by salt caverns.