We have consistently worked towards establishing an advanced level insight into the 3D structure of proteins. Key questions are: where are particular residues located in the protein, and does solvent accessibility have any influence on the probability of finding a residue in a particular location. Classical protein design answers can be derived from such studies, such as: where are S-S bridges located in proteins, and which conformation do they adapt; which residues can be mutated on a protein surface and what is the typical substituent. (Teresa Neves Petersen, Peter Fojan, Steffen B. Petersen)