Purpose - The purpose of this paper is to present the Swiss Cooperative Storage Facility, a high bay, high density, automated, and oxygen reduced off-site storage facility which serves five research libraries from the German speaking part of Switzerland; it opened in February 2016. Design/methodology/approach - It describes the complete process of evaluating and planning this innovative facility. Findings - It explains the way the cooperation of the five libraries in highly federalist Switzerland was achieved, what principles guided its organization, and how the libraries prepared their holdings for this off-site storage. It shows the construction as an ecologically driven green building with economical advantages. Originality/value - The project seems to be the second automated and oxygen-reduced library storage facility worldwide, after the British Library's Additional Storage Buildings, and the depth and detail of the evaluation phase is new.