In the U.K. the National Audit Office has produced a report into the Government's £1.2 bn anti-drug strategy. It conludes that every £1 spent has brought £2.50 worth of benefit. Between 2004-5 and 2008-9 the number of adults in effective treatment rose from 134,000 to 195,000 and the number of problem drug users completing their treatment free from dependency rose from 6,000 to 15,000. However, of the 12,500 people who entered a programme aimed at getting drug users back into work early only 8% kept a job for 13 weeks or more. The report also criticised the lack of a framework for evaluating the success of the strategy saying that this made it difficult to accurately assess its success.
You can download a copy of the National Audit Office report at