Corrections appears to be winning the war on drugs, with new figures showing drug use in prison is on the decline.
Each year about 4500 random drug tests are carried out on inmates, with some going to extreme lengths to get the drugs inside.
Figures obtained by 1 NEWS under the Official Information Act show 155 inmates returned positive drug tests, which is almost half the number from seven years ago.
The majority were caught using cannabis, followed by amphetamines and opiates.
"Drugs and alcohol are a significant driving force behind much of the crime that we see in this country and much of the offending behaviour. So we've got our part to play in helping to reduce that," says Chief Custodial Officer Neil Beales.
More than 1000 offenders have completed intensive alcohol and drug treatment programmes this year, with Corrections spending $8.6m on aftercare support.
"It's not just about health it's about safety," Mr Beales says.
"It's about people being stood over, it's about people on the outside being pressured by criminals and gangs to bring drugs in so the scourge of drugs is far and wide."