Objectives: To investigate differences in participation with breast and cervical cancer screening related to individual socio-economic characteristics, across population-based versus opportunistic screening programmes.Methods: Data from Eurobarometer 66.2 "Health in the European Union" 2006 on self-reported breast and cervical cancer screening participation in the preceding 12 months within the EU 15 was obtained The sample was restricted to those eligible for screening based on the screening age within each country. Observations for 2214 and 5025 individuals respectively for breast and cervical cancer screening were available. Data on marital status, self-reported health. socio-economic group and years of education were also available. Screening programmes were categorised as population-based or opportunistic and logistic regression analysis used to examine the relationship between participation, individual characteristics and programme type.Results: Differences in participation related to socio-economic status were observed in opportunistic screening programmes for breast cancer (OR = 0.63* and OR = 0.51**) and cervical cancer (OR = 0.75** and OR = 0.64"). Differences related to socio-economic characteristics were not found with respect to participation in population-based programmes.Conclusions: In opportunistic programmes, differences in participation across socioeconomic groups are evident in respect of both breast and cervical cancer screening. These differences may have implications for treatment and outcomes across socio-economic groups. Such differences were not evident in population-based programmes. (C) 2011 Elsevier Ireland Ltd. All rights reserved.