Portuguese wine regions are grouped into three levels of classification. At the top are the Denominação de Origem Controlada (or DOCs) which are Quality Wines Produced in Specified Regions (QWpsr) under the European Union wine regulations and thus correspond roughly to the French Appellation d'origine contrôlée (AOC) and Spanish Denominación de Origen (DO) classifications. The second group consist of Indicação de Proveniencia Regulamentada (IPRs), and are also QWpsr. IPRs are used for DOC candidates "in training", and this level roughly corresponds to the French Vin Délimité de Qualité Superieure (VDQS) system. The final group are the Vinho Regional (VRs), which are table wines with a geographical indication under EU regulations. VRs each cover a larger area and are similar to the French Vin de pays at regional/departmental level.
The early 2000s has seen many changes in the classification and naming of Portuguese wine regions. Many previous IPRs have been elevated to DOC status, either on their own or to create a new, larger DOC from either IPRs or a mixture or smaller DOCs and IPRs. At the same time, the name of some VRs have been modified to allow them to be differentiated from some newly created DOCs which have taken over names of former VRs.
As of 2009, there were 26 DOCs for wine (not counting special designations and subregions), 4 IPRs and 11 VRs.
Some former separate DOCs have been absorbed into larger DOCs:
While many former IPRs have been elevated to DOC status under the same name, some have instead been absorbed into larger DOCs: