Canine Leishmaniasis (CanL) is endemic in Campania Region (Italy) and is strictly related to Human Visceral Leishmaniasis. Past and present reports of the prevalence in the Region show that exist places were CanL has been known for a century (Vesuvius and Ischia Foci) and other localities where the disease appears to be recent (Caserta and Salerno provinces); moreover, the zoonosis is seen not only in endemic foci (autochthonous), but also in non-endemic areas (imported cases), for example in the Benevento and Avellino provinces. Two zymodemes have been identified in human and canine population and also in sandflies: MON 1 and MON 72. Endemic or stable CanL foci correspond with Vesuvius Area, Ischia island, Maddaloni and neighbouring Commons, other foci in the Salerno province. These foci are associated with optimal ecological condition, abundance of reservoirs and hosts, abundance of phlebotomine vectors, prevalence in canine population around 10-40%, incidence in canine population 5%, risk for human population 0.002%. Instable foci occur at the border of the stable foci: they may be the result of changes in climate with the occasional introduction of infected dogs in the areas; in the foci are registered low presence of phlebotomine vectors, prevalence around 0.5-3%, sporadic human cases. Today, in Campania region CanL undoubtedly has an increased incidence and a wider geographic distribution than before: new cases are now reported in areas that were previously non-endemic. Ecological, demographic and environmental changes, large population movements, urbanization have led to an increased incidence and to importation into suburbs with high densities of people and sand-flies. These changes include "global warming", increased number of stray dogs, dogs and population movements, changes in human population (increased number of immune-depressed and old people). Nowadays, the most important focus of CanL and Human Visceral Leishmaniasis of the Mediterranean area is located in Campania Region: during the year 2000, 143 cases of Human Visceral Leishmaniasis have been recorded in Italy, an half of them (83 cases) in Campania region.