The objective of this study is to estimate the volume and pattern of illicit financial flows money that is illegally earned, transferred, or utilized from all developing countries based on a critical review of competing models. Through a process of testing various combinations of these models and employment of a two-stage filter for elimination of spurious data, this study presents a range of estimates of illicit financial flows from developing countries from 2002 through 2006. While all developing countries which report relevant data to the International Monetary Fund (IMF) and the World Bank are included in the study, salient deviations from the regional classification used in the IMF's International Financial Statistics are noted in the paper. Overall findings indicate that illicit financial flows are growing in volume on a yearly basis with the largest recorded outflows coming from Asia and Europe. The Middle East and North Africa regions demonstrate the fastest yearly growth. While the methodology employed in this study has produced reliable estimates on illicit financial flows based on the most recent data available, the authors note that estimates of illicit financial flows based on existing economic models are likely to understate the actual problem because official statistics cannot capture all of the conduits for sending capital out of a country.