The volume brings together the contributions from the conference "Fortress in Focus - Mathematical Methods in the architectura militaris of the 16th and 17th centuries and their Sublimation in the architectura civilis," which took place in October 2008 in Dresden as a collaborative project between the Institute for Art History at TU Dresden, the Institute for Art and Image History at Humboldt University Berlin, and the Mathematical-Physical Salon of the State Art Collections Dresden. A bastion fortress or fortified town posed a central challenge for contemporary theoretical and applied sciences. Its planning required an unprecedented level of organizational, surveying, and design effort. The elements of the fortress belt had to be arranged in such a way that mutual coverage and uninterrupted sightlines were ensured.