Roadside tests for drug driving are to be carried out by North Wales Police as part of a research programme (BBC News).
The tests will be purely voluntary for drivers, with the results used for statistical purposes only to find out the extent of the problem.
Chief inspector Gary Ashton said: "We intend that this trial will help us build an accurate picture of driving under the influence of illegal drugs."
Devices from drug testing company Concateno will be used in the trial, with a test for up to six different drugs in a single oral fluid sample. It takes around 30 seconds and results will be available within five minutes.
Click here to read the full BBC News report.