Pamela - I cured my son of not cleanning his room when he was told to in a very unconventional way. I don't know how old your son is but mine was old enough to go with friends and do things.
He was invited to go skating with a group of friends. I told him he had to clean his room first and he didn't do it.
His friends came to the door and I told them, "Joe has a problem, he didn't clean his room this morning when he was told. That means you guys have options."
"#1 - you can go without him"
"#2 - you can pull up a chair and watch him clean his room, I have plenty of chairs and room in the hall outside his door."
#3 - you can roll up his sleeves and pitch in and help. I honestly don't care who cleans his room, he just isn't going until its nice and neat."
All of a sudden there were about 5 other kids in addition to my son vacuming and folding clothes and dusting and making the bed. I could tell the other kids were not happy about it but they didn't want to wait for him to clean by himself.
In the future whenever I told him to clean his room he knew I meant it and he didn't want a replay of his friends having to clean it.