Poisoning protected birds was an issue, said the review - Pic RSPB/PA wire
More needs to be done to prevent the poisoning of birds of prey in Scotland, police and prosecution inspectors said.
It said some parts of the country, such as Grampian and Tayside, had been working to clamp down on the illegal activity on lucrative grouse moors.
The findings came after the Scottish Government announced a six-month review of wildlife crime.
The inspectors also said all police forces should appoint full-time wildlife crime officers.
The joint publication of the report, by Her Majesty's Inspectorate of Constabulary and Inspectorate of Prosecution, also urged ministers to put a new national plan in place to combat the problem.
The review was launched by Environment Minister Mike Russell after several high-profile wildlife crime incidents in 2007 such as raptor poisoning, poaching and hare coursing.
Its most controversial aspect was the impact of birds of prey in areas intensively managed for grouse shooting - where conservationists can clash with those running what is a multi-million pound Scottish industry.
The inspectors' report stated: "Some success in preventing illegal activities had been made, most notably in Grampian and Tayside, by bringing together all relevant parties to form partnership groups.
"In other parts of Scotland, little sustained progress was evident."
Mr Russell, who will make a more detailed response to the Scottish Parliament at a future date, said there were signs of positive changes to Scotland's "unacceptable" wildlife crime rate.
"A crime against Scotland's rich and unique natural heritage is a crime against Scotland itself, be it poisoning a bird of prey or badger baiting," he said.
But the minister added: "I have been particularly encouraged by a growing willingness on the part of groups with an interest in the countryside to put aside their differences and to work together to address the issue of wildlife crime."
Louise Robertson, of the League Against Cruel Sports, said the report outlined some "very positive steps" which would help prosecute those responsible for wildlife crime.
She added: "We are particularly pleased with the recognition that wildlife crimes are to be managed like any other crime."
Colin Shedden, Scottish director of the British Association for Shooting and Conservation, said: "We have been concerned for a number of years about the apparently difficult relationship between shooting interests and those investigating allegations of wildlife crime.
"It's time to break down those barriers and work together for the good of the Scottish countryside and economy."
Duncan Orr-Ewing, head of species and land management at RSPB Scotland, said: "We support proposals for a full time serving wildlife crime officer in every Scottish police force, as in our experience this improves wildlife crime detection, enforcement and prevention."