The OPEX was held in the Gulf of Antalya in the Eastern Mediterranean between 09-20 October to support MARSEC COE’s concept development efforts under the umbrella of EXER MARSEC-23. Our former President and president of YATA International Selin Yılmaz, and President of YATA Turkey, Mustafa Eracar attended OPEX on behalf of YATA Turkey. We would like to thank the MARSEC, MARSEC personnel, and Naval Forces Command.