Since the concept of Pharmaceutical Care was introduced from United States about twenty years ago, this initiative has become a dominant form of practice for thousands of pharmacists around the world. Currently, pharmaceutical care is understood as the pharmacists' compromise to obtain the maximum benefit from the pharmacological treatments of the patients, being therefore responsible of monitoring their pharmacotherapy. As the profession has moved from a product orientation (dispensing medications) to a patient focus, clinical training requirements have expanded. This is a slow but ongoing process, which started from a philosophical point of view, in order to transform the concept of Pharmacy from commodity-based, mercantile operations into a clinical profession in the community pharmacies. Since its introduction, there has been an ample debate on the definition of pharmaceutical care due to differences in Pharmacy systems and in health care structure among the different countries. Moreover, several implementation barriers exist, which are attributable to problems in education, skills, resources and environment. Indeed, an awareness of the problem resulting from the use of medicines exists and numerous studies reflect that drug use control is necessary since there is an important relationship between morbidity / mortality and pharmacotherapy. Thus, it is possible to evaluate the benefits of pharmaceutical care on patients' health and ultimately on society. Many studies have been conducted, which show that the provision of pharmaceutical care has its value in common pathologies such as diabetes, hypertension, asthma, hyperlipidemia, chronic pain, rheumatic diseases or psychiatric disorders, as well as in polymedicated patients. A large amount of data is currently being published in biomedical journals, in an effort to establish the clinical, economic and humanistic viability of pharmaceutical care. Thus, the aim of this review is to study the evolution of this practice from its beginning until nowadays. Furthermore, we have analyzed a number of implementation programs performed in countries of Europe, the United States and Latin America, focusing on clinical, economical and humanistic outcomes, and also, on the current concept of drug therapy problems (DTP) considered as failures in drug therapy. We conclude that the positive outcomes obtained with different programs of pharmaceutical care are making a beneficial change in patients' health but still more research projects should be conducted to support this change.