I definately think that corruption does exist in every country. People with power will be tempted to be corrupted; that is the way it is. Some people can fight this urge, but not many.
I think it is a necessary for people in power to be held responsible for their actions. That is why i believe that governments and large corporations etc. have agencies in place that continually police the actions of the high profile executives and politicians etc.
I know that even that can have its downfalls; but in a lot of cases the corrupt will be caught.