The remarkable proliferation of new techniques and the diversification of existing ones have resulted in explosive growth within various branches of cell biology. Consequently, cell biology and molecular genetics have become inseparable disciplines. Suffice to say molecular biology is a combination of both of these contemporary branches. The molecular approach has penetrated every traditional field of biological sciences, including medicine. The foundation of many fundamental discoveries has been based upon studying the cell at the subcellular level. For several decades, extensive studies on prokaryotes have provided an understanding of the fine structure of genes. However, who could have ever imagined, even a decade ago, that eukaryotic genes could be spliced, cloned and even re-designed. Recent recombinant DNA technology has opened new vistas toward understanding the linear order of genes on eukaryotic chromosomes; an idea that was once inconceivable.The main purpose of the series, Advances in Genome Biology, is to keep abreast of the latest developments in the field and to further nurture and promote the linkage between newcomers and existing researchers. Each volume shall address a specific theme, depicting current progress and future investigative directions pertaining to genome research. Furthermore, this inaugural issue has attempted to elucidate the importance of the various molecular techniques currently being applied in an effort towards deciphering the genome.A complete account of the numerous available techniques, within the scope of single volume format, would be a herculean task. Therefore, I have chosen only the topics, which will have the greatest interest to the majority of investigators. In fact, the progress in molecular techniques has advances so rapidly that each method could easily occupy a single volume.