Herpes zoster (HZ) is a disease characterized by an acute vesicular dermatitis, with a typical unilateral ganglion distribution, due to the reactivation of the varicella zoster virus (VZV) acquired during the primary infection known as chickenpox or varicella. VZV has a ubiquitous spread, and most adults have the virus in a latent form and are at potential risk of suffering an episode of HZ during life. The onset of HZ is closely related to a decline in VZV-specific cell-mediated immunity, which increases with age. HZ is therefore a very common disease associated with serious complications (e.g., post-herpetic neuralgia) and with a negative impact on the quality of life of patients. Early diagnosis is sometimes difficult and the therapeutic approach is often suboptimal. As the proportion of frail and elderly people is progressively increasing, a growing impact of HZ and its complications can be expected. For all these reasons, prevention is essential. Immunization allows to effective reduction of the incidence and severity of HZ and is an example of how adult and elderly vaccinations are an integral part of the preventive strategy of infectious diseases, which must be addressed to all age groups of the population.