The results of the genome projects and the obvious problems with handling, storing and interpretation of generated data pose a lot of pressure on existing strategies in drug target discovery and development of new therapeutic concepts. Genomic data, i.e. DNA/RNA sequences identified by subtractive expression pattern analysis, are not enough per se for a clear identification of a therapeutic target, mainly because proteins and not DNA/RNA are the loci for drug mode-of-action. The effects seen on the gene expression level are only a response to drug effects on the protein level. In addition, there is not always a direct correlation between gene expression and protein expression. Therefore, the major focus of current efforts in drug discovery is the linkage between the genes and the function. One of the most powerful technologies for this purpose is now evolving and has been designated as Proteomics.