The Prado-Recoletos axis is the main historical boulevard in Madrid, which contains the most important concentration of art museums in all of Spain: the Museo Nacional Centro de Arte Reina Sofía, the Museo Nacional del Prado and the Museo Nacional Thyssen-Bornemisza. In the last years, they have undergone extensive renovation. The different renovation projects can be used to examine how museum libraries today juggle the needs of their users while addressing the challenge of providing the services of a modern research library. The new State Museum Libraries Network (BIMUS) has been an important factor in this development.