Audit Scotland has raised concerns over funding and disparity in service costs across the country in its report, Reducing Offending in Scotland.
Reoffending rates have been quite static, with 30% of those convicted in 2009-10 committing another crime within a year, compared with 32% in 1997-98.
Latest figures from 2011 also show 22% of offenders had at least 10 previous convictions.
The watchdog claims Community Justice Authorities, set up in 2007 to help tackle reoffending, struggled to achieve their goals due to the way they were set up and inflexible funding.
It also states services in different authority areas vary widely in terms of costs, for example probation reports ranging from £951 in South Lanarkshire to £2887 in Renfrewshire, when the average is £1613.
The report has prompted anger from opposition parties, who claim the Scottish Government has to "get a grip".
Scottish Conservative MSP John Lamont said: "The Scottish Government knows what works to reduce reoffending, but the money is not being targeted towards effective programmes and there has been no assessment of the performance of our criminal justice authorities.
"The Scottish Government needs to get a grip of the problem and start spending public money more wisely on projects with a proven track record of success."
Scottish Labour MSP Lewis Macdonald added: "The report highlights the lack of provision, education and support which increases the chance of re-offending. It is worrying that effective programmes are not being implemented and the SNP need to get a grip. With a rising prison population, the SNP need to ensure that justice works."
A total of £128 million was spent in 2010-11 by the Scottish Government, Scottish Prison Service and CJAs to try to reduce reoffending – less than one-third of the £419m spent dealing with convicted offenders.
The report shows millions could be saved if service costs were brought into line with average costs throughout Scotland.
A Scottish Government spokesman argued that reconviction rates are at their lowest levels in 13 years – despite the marginal drop.
He added: "The second phase of the Reducing Reoffending Programme, launched in April, is already addressing Audit Scotland's recommendations with specific projects on funding, performance measurement and structures."