Quality health care has a cost with three components: the cost of the diagnostic or therapeutic procedure itself, the cost of error or side effects prevention, and the cost of error or side effects treatment. Hence an optimal position must be found. The literature shows that quality projects aiming at decreasing the cost of side effects treatment usually lead to savings. On the other hand, legal or contract requirements aiming at preventing side effects from happening usually lead to additional costs. Therefore, specific assessment methods to compute the costs and benefits of quality programs must be developed. It would be paradoxical to waste resources in setting up and running a quality assurance program.