Pharmacovigilance is defined as the pharmacological science that is relating to the detection, assessment, understanding, prevention of adverse effects, particularly the long term &short term adverse effects of medicines. The Pharmacovigilance is the important and integral part of clinical research. This article describes and discusses the aims, objectives, role, need for the Pharmacovigilance, different Pharmacovigilance programme, various Pharmacovigilance methods, Pharmacovigilance reporting and functioning.