The assessment of agricultural policies depends more and more on micro-economic data sets. This is especially true for policies with an income objective in a situation where farm households have different income sources. Among others the OECD has stressed this point in recent years with analytical reports. The PACIOLI network yearly brings together data managers and researchers interested in the innovation of data collection in this area. In April 2004 a joint workshop was organised at the OECD in Paris to bring experts together to exchange best practices. This report contains the proceedings of that workshop.