To begin with, building plans had to be drawn up as a basis for a true to original rebuilding of the Frauenkirche. The aim was to rediscover the church's geometry that was lost with its destruction, to transfer this into building plans and to improve the bearing structure where necessary.
 
Fortunately, a number of sources existed to assist in this work. Archives still contained historical plans and horizontal projections that could be evaluated. Restoration work in the 19th and 20th century had also been documented in the form of site measurements and photos. In 1993, photogrammetric pictures were taken of the ruin to reconstruct the spatiality and three-dimensional shape of the Frauenkirche. This technique was also employed in a different way for the reconstruction of the dome geometry, where historic photos were used due to the lack of old plans. Finally the ruin itself together with the large structural parts and individual pieces that could be recovered proved a great source of information.
 
An initial three-dimensional model was created based on the recovered data using the latest computer technology. This was a real challenge, not least due to the baroque architecture with its multiple curved surfaces. But no matter how indispensable the computer was as a working tool, it could not replace the creativity of the architects and engineers. Their skills were in great demand with regard to planning and calculating the stability and structural safety. 
 
As a result, the rebuilding of the Frauenkirche closely followed the traditional and meticulously reconstructed bearing structures, but corrected former shortcomings in a number of places. For example, various workmanship quality levels were defined for the masonry, a tension ring of steel was integrated with special anchors at the base of the inner dome and the number of ties (steel rings too) which help keep the dome together was increased. The galleries  are no longer borne by timber beams but steel girders (as had already been installed during the restoration in the 1930s) instead. Furthermore, the connection between the gallery girders and the masonry was improved.