Personalized medicine is coming step by step to real clinical practice. The new era is forthcoming, in which 'one size does not fit all'. The hopes and expectations predominantly are based on achievements of molecular biology. Close connection between therapy and corresponding diagnostic test can lead to better defining patients target groups. Moreover, biomarkers defining is becoming a new approach to therapy stratification. Viral, oncologic, inflammatory and metabolic diseases are the examples of Roche involvement in this strategic way of development.