Stimulation of collateral artery growth is an attractive alternative treatment modality for patients with coronary or peripheral artery disease. Decades of basic research have led to a reasonable understanding of the mechanisms behind collateral artery growth although 'bench research' is still absolutely warranted for better understanding. It is some 7 years ago that the first clinical trials on therapeutic manipulation of the collateral circulation were published and this field is still relatively new and in large parts unexplored. Arteriogenesis, namely the growth of large collateral conductance arteries, seems to be the best biological substrate candidate for therapeutic manipulation. Future studies in this field will have to cope with problems of substance choice, clinical detection methods and unwanted side-effects.