The separation surgery of the Egyptian conjoined twins -- Hassan and Mahmoud, scheduled for today, began at King Abdulaziz Medical City of The National Guards in Riyadh. On the basis of a directive of the Custodian of the Two Holy Mosques, King Abdullah bin Abdulaziz Al Saud, the separation of the Egyptian conjoined twins- Hassan and Mahmoud, has been undertaken by a Multi-disciplinary team headed by Dr. Abdullah Al Rabeeah, Minister of Health along with specialists in Neuro Surgery, Anesthesia, Plastic Surgery, Pediatric Surgery, Nursing and technicians. The separation will take approximately 15 hours and will have seven phases with a 70% success rate. The phases will first start with Anesthesia, followed by sterilization, Separation of intestines, Urological Separation, Genital Separation, Joined Lower Extremity Separation, Pelvis Separation, Twin Separation and finally Organs Reconstruction. The twins arrived in Riyadh from Egypt on February 10, 2009; they are conjoined at pelvis and require separation of their abdomen, intestines, urinary and genital tracts. King Abdulaziz Medical City, Riyadh has become internationally acclaimed for the separation of conjoined twins. Hassan and Mahmoud will mark the twenty-first separation surgery that has so far taken place.