To date, the COMS remains the largest study ever to be performed in ocular oncology. The COMS enrolled patients from 1986 until 1998, with clinical follow-up continuing until 2003. It was a multicentered study comprising 43 participating clinical centers in North America, with centralized units dealing with echography (North Carolina), photography (Iowa), pathology (Wisconsin), radiation physics (Texas), and general coordination (Maryland). Over a period of years, numerous studies, as well as several editorials, letters, and review articles, have been published based on the findings of the COMS that have made a tremendous contribution to the field of ocular oncology. They showed us that for medium-sized tumors, enucleation and plaque brachytherapy with iodine-125 yielded equivalent survival outcomes. The results of this arm of the study imparted huge impacts throughout the continent, and the world, as many centers transitioned to an eye-sparing therapy. Second, they concluded that pre-enucleation radiation did not reduce mortality in patients with large tumors, compared to enucleation alone. While the COMS answered several questions, there are still several that remain controversial to this date. The COMS did not address the treatment of very small tumors as these were excluded from the study. Additionally, they did not evaluate treatment of tumors located around the nerve nor did they study the utility of radiation therapy for very large tumors.