More than a century after Catalan architect Antoni Gaudí began working on the Expiatory Church of the Holy Family, Sagrada Família remains under construction. This catalog focuses on that dynamic and ongoing process, and on the successive builders’ incorporation of new technologies into the structure´s magnificent design, a living work of performance in itself. It documents the cathedral’s evolution using handmade drawings, plaster models, digital imaging, and 3D modeling. It examines the geometries and formal languages that have informed generations of architects and builders. At the same time, it shows the integration of traditional craftsmanship with the most cutting edge computer graphics and robotic engineering. Originally situated on the outskirts of the city, La Sagrada Familia today serves as the enduring symbol of Barcelona. But unlike the Eiffel Tower or Brooklyn Bridge, Barcelona’s icon is still a work in progress and a magnetic center of spiritual life.