Cervical cancer is the fifth most common cancer in European women. The recognition of a viral agent such as Human Papillomavirus (HPV) as a necessary cause in the development of cervical cancer implies that this disease may be prevented by effective prophylactic or therapeutic interventions against this infection. HPV vaccines conferring protection against infection with oncogenic HPV types 16 and 18, which cause the majority of the cervical cancer cases, are currently marketed, but. continued cervical cancer screening is necessary regardless of vaccination. Organised screening programs have the highest potential to reduce cervical cancer mortality, by achieving higher levels of coverage of all population groups and higher proportions of women screened at regular intervals, with better costeffectiveness and overall quality. Opportunistic screening, on the other hand, has a more limited impact and is more difficult to monitor and to evaluate due to its decentralized nature and lack of systematic reporting. However, opportunistic screening is still predominant in most European countries. In Portugal, cervical cancer screening has been predominantly opportunistic, except for regional organised programs in the Central Region of Portugal, in the region of Alentejo and an organised screening program is also being implemented in the North region of Portugal.