Unfortunately, despite efforts to fix the problem, it's still happening.
In fact, one report out says wrong-site surgeries have gone up seven-fold in the last 10 years.
That could be due to better reporting of problems but, even so, it shows the errors aren't going away.
For patients like Doug McCoy, whose doctors operated on the wrong ear, it's hard to accept.
"A mistake like that simply shouldn't happen," McCoy said. "It's a 50-50 chance, it's not rocket science."
Medical watchdog organizations have tried to reduce errors with universal procedures, such as marking areas of the body to be operated on, or having an operating room checklist.
New research from the VA also shows that 'open communication', giving everyone the chance to bring up any concern, helped the most.