In my observation, 'corruption' is pretty much universal. It seems to be a function of being a human in a society larger than a typical hunter/gatherer group, and it makes a lot of sense why this would be the case.
Seems to me that it is 'better' to have the corruption be pushed down to the lowest level possible. In this case more of the money stays at the local level. In the U.S. where the corruption lives more at the state, federal, and corporate levels, the 'trickle down' path for the stolen money is so long that little or none of it goes back to the community. On an individual level most people get all of the mine-shaft and little or none of the mine.
In this case, corruption can be reduced to a minimum level when everyone's self-conscience can perceive and implement such high concepts as the common good, self-improvement, justice. So how to achieve this?
My solution would be a 'social contract' with zero-tolerance and with teeth. Teeth which look like a 7.62 and a brick wall.
You choose to work for the public, you work for the public good. Period. If you cannot stand the heat then stay out of the kitchen. There is now a ton of technology to spy on people. It should be keeping tabs on public sector workers or contractors who get paid out of the public coffers (both being a choice people are free to make), and specifically NOT the people who choose to remain in the private sector. Right now the opposite is the case.