"Precision medicine" and "personalized medicine" constitute goals of research since antiquity and this was intensified with the arrival of the "evidence-based medicine." precision and personalized psychiatry (3P) when achieved will constitute a radical shift in our paradigm and it will be even more transformative than in other fields of medicine. The biggest problems so far are the problematic definition of mental disorder, available treatments seem to concern broad categories rather than specific disorders and finally clinical predictors of treatment response or side effects and biological markers do not exist. Precision and personalized psychiatry like all precision medicine will be a laborious and costly task; thus the partnership of scientists with industry and the commercialization of new methods and technologies will be an important element for success. The development of an appropriate legal framework which will both support development and progress but also will protect the rights and the privacy of patients and their families is essential.