The article presents the International Population Policy Acceptance Survey database (IPPAS) which contains information gathered from 35377 respondents (16470 men and 18877 women) in 14 European countries (Belgium (Flanders), Czech Republic, Germany, Estonia, Italy, Cyprus, Lithuania, Hungary, The Netherlands, Austria, Poland, Romania, Slovenia, and Finland). Its main aim is to highlight opportunities for the analysis of information collated and discuss challenges and lessons learned about the difficulties in constructing a large international comparative database. The IPPAS database is the key instrument for the internationally comparative study of values and attitudes concerning five broad domains: (1) general family related policies and attitudes; (2) gender roles in partnership, family life and work and opinions about government policies with respect to gender related rights; (3) reconciliation of work and family life as it relates to the combination between employment, housework, child care, and care of elderly; (4) attitudes and experiences about having children and child-friendly policies; (5) and attitudes, experiences and expectations regarding intergenerational solidarity, elderly, one's own old age and population ageing. Despite agreed recommendations with respect to the sample design, the standard questionnaire and coding procedures, not all countries complied strictly to these recommendations due to a variety of conceptual, organisational, financial and/or methodological reasons. Notwithstanding its limitations, the IPPAS database is the unique source of information, which covers a broad array of attitudes, preferences and expectations on population trends and policies and allows not only for comparative analyses of attitudes on population trends and policies among 14 European countries, but includes also the opportunity to make use of the pooled and weighted data to explore and study specific population problems or population subgroups. Moreover, it offers the opportunity to thoroughly and comprehensively analyse the recorded data, also in combination with its two other major project components of the DIALOG Project - the Delphi Study on the exploration and analysis of expert opinions on population policy development at national and European levels, and the contextual analysis and desk review of literature and secondary sources.