Quaranta anni di valutazione delle politiche e degli investimenti pubblici: lezioni dall’esperienza - This is a review article based on 40 years of experience in the field of policy and project appraisal and evaluation. The author has had an extensive career in this area in the World Bank, the European Commission, Italian Government Ministries and in academia. The review concludes that cost benefit analysis extended to "real options" and applied jointly with the "effects method" helps solve certain critical issue of traditional financial and economic appraisal and evaluation techniques. More significantly, it contributes to better integrate financial and economic evaluation and appraisal techniques with organizational and sociological evaluation techniques. Key words: appraisal, evaluation, World Bank, distribution weights.