"Large machine-readable census micro-data samples exist for many countries, but access to these data has been limited and the documentation is often inadequate. Even where such micro-data are available for scholarly research, comparisons across countries or time periods are difficult because of inconsistencies in both data and documentation. IPUMS-International addresses these issues by converting census micro-data for multiple countries into a consistent format, supplying comprehensive documentation, and making the data and documentation available through a web-based data dissemination system."