One Country One Library (OCOL) is an idea to turn countries into open digital libraries via geographic coordinates and to measure the impact of reading materials in each country. The platform, available as a web and mobile application, houses all types of materials, including books, academic journals, general articles, short stories, and guides. It serves as a digital reading room, a self-publishing platform, a learning tool, an information kiosk for tourists, and a powerful new evaluator of the materials' performance and reader activities. Publishers are paid a participation fee per country and supplied with detailed analytics showing each publication's score and impact. This issue of Library Technology Reports (vol. 56, no. 7) sheds light on the idea as well as on the technology and the business model designed to make the idea sustainable for participating countries, libraries, publishers, authors, and organizations. The goal of the report is to present the OCOL idea in its simplicity as well as its complexity and to encourage librarians and other book professionals to consider building open national digital libraries that serve the needs of the widest possible range of users.