This report reviews the "Economics and Social Impact Study of the Proposed Gambling Bill" conducted by the Henley Centre and published in February 2004. The Henley Centre report is an ambitious attempt to quantify the impact of the proposed Gambling Bill. The purpose of this review is to evaluate the findings of the Henley Centre report. Specifically, a full discussion of modelling and methodology is given. Where appropriate the wider existing literature is drawn upon in order to place the Henley Centre findings in context and a section discussing the limitations of the analysis is included. Finally, a discussion of the Henley Centre report content within the context of the policy regime that will result from the Gambling Bill is provided. The Henley Centre report is a comprehensive and detailed analysis of all the sectors of the gambling industry and in this respect is an important study. There have been many studies that have looked at individual parts of the industry but fewer that give such a detailed picture of the entire betting and gaming industry [notable exceptions being the Gambling Review Body Report (2001) and a KPMG report (2000)]. Not only does the Henley Centre report consider all the sectors within the betting and gaming industry but the impacts to the wider leisure and entertainment market are also considered. In the context of the proposed Gambling Bill this is important given that it constitutes a sizable modernisation to the industry such that all sectors will be affected (in one way or another). Moreover, there are likely to be important spill over effects across sectors and into the wider leisure industry that a partial analysis would not capture. Finally, the Gambling Commission will be faced with a complex set of changes in behaviour as it attempts to pursue the principles of the proposed legislation. The Henley Centre report is therefore a valuable contribution to the debate regarding the proposed Gambling Bill. There are, however, a number of ways that the report could be improved. The most obvious means of improvement would be the inclusion of a technical appendix. Presently most of the statistical details of the economic modelling are missing and this means the findings cannot easily be evaluated. Whilst the predictions are based upon statistical modelling none of the details of the modelling are reported. Without being able to evaluate the methodology it is difficult to comment on the accuracy of the findings and therefore the findings cannot be confidently used to inform policy. Whilst it is appropriate that the Henley Centre should produce a non-technical version of the analysis, this ought to contain a comprehensive technical appendix that would allow the results to be assessed by a competent expert. Unfortunately this technical appendix is missing from the Henley Centre report and this places limitations on how the findings can be utilised within the debate and ultimately how they can be used to inform policy. A search of the Henley Centre's web page www.henleycentre.com and requests by DCMS to elicit information also failed to uncover any more details of the statistical components of their report. This review highlights what statistical analysis ought to be included in the report to enable policy makers to effectively utilise the reports findings. The reader should note that it may be the case that the Henley Centre has undertaken the statistical practices called for in this review and simply neglected to include the output in their final report. In other cases there may be suggestions for improvements.