The Kent head teacher who pioneered random drugs-testing at his school is to lecture President Bush's advisers at the White House next month.
Mr Walker has just retired as head teacher of Abbey School
Peter Walker has just retired after spending more than 20 years as head of the Abbey School in Faversham.
He was responsible for a random drugs testing scheme at the school which began in January last year.
Mr Walker said he would be giving advice to the US drugs tsar about anti-drugs measures in schools.
He said: "They [the Americans] are looking for ways that can work, and one of the keys to the way in which ours works is that parents have a right to say no to testing and students have too, separately from their parents."
Mr Walker has said the testing of pupils for drugs helped Abbey School achieve its best-ever GCSE results last year.
About 500 tests have been carried out so far, with only one pupil testing positive.
Mr Walker has suggested that more schools should bring in the tests.
"Very few schools actually put their heads above the parapet because once you get involved in this kind of thing some people, wrongly, believe that that school has a problem.
"Every school has a drug problem. The thing to do is to be open and honest about it and tackle it.
"Prevention is far cheaper and far more effective than having to cure," he said.