The increasing of healthcare services complexity over the past decades, and the increasing of the healthcare coverage has led to a corresponding rise in the number of reported adverse events, unintended injuries and medical errors that might be more serious than the disease itself. Concurrently, developing of the quality management concepts ensured the applications of good documentation and reporting systems, which helped in identifying the size of the problem, such as in the famous report of the US Institute of Medicine "To Err is Human: Building a Safer Health System." This huge size of reported medical errors recognized by WHO as one of the key issues facing healthcare services. Consequently, led to establishment of World Alliance for Patient Safety at the start of the 21st century. The Alliance considered the importance of improving the safety of surgery as the second global patient safety challenge in 2008. Patient safety systems as a public health issue are challenging in all levels; in development of evidence based standards, implementation and assessment.