Rear Adm. Gilday is a surface warfare officer and has deployed across the globe in destroyers, cruisers, and aircraft carriers. Tours at sea include command of Destroyer Squadron Seven as sea combat commander for the Ronald Reagan carrier strike group as well as command of the destroyers USS Higgins (DDG 76) and USS Benfold (DDG 65). Both ships earned the Battle Efficiency "E" Award. He also made deployments while serving in USS Gettysburg (CG 64), USS Princeton (CG 59), and USS Chandler (DDG 996).

Gilday’s shore assignments include the Bureau of Naval Personnel, the staff of the Chief of Naval Operations in Strategic Plans and Policy Directorate, and the staff of the Vice Chief of Naval Operations.

His joint assignments include the White House where he served as naval aide to the President and the joint staff as executive assistant to the Chairman of the Joint Chiefs. As a flag officer, he served in joint posts as director of Operations at NATO’s Joint Force Command in Lisbon, Portugal, and as chief of Staff for Striking and Support Forces NATO.

A native of Massachusetts, he is a 1985 graduate of the U.S. Naval Academy and earned master’s degrees from the Harvard Kennedy School and the National War College in Washington, D.C.

Gilday assumed command of Carrier Strike Group Eight in June 2013.

His decorations include the Defense Superior Service Medal, Legion of Merit, Bronze Star, Navy and Marine Corps Commendation Medal with Combat ‘V’, Combat Action Ribbon, and additional individual, campaign, and unit awards.