The destroyer arrived Efate 7 March and after a short rest screened a task group during the strike on Kavieng, New Ireland, 20 March. Returning to Efate 25 March, she joined some 200 ships for the largest operation yet attempted in the southwest Pacific, the occupation of Hollandia. "Harrison" arrived New Guinea 1 April, engaged in patrol and escort operations until 19 April, and then sailed to Humboldt Bay for the assault. Carriers screened by the destroyer and her sisters bombarded enemy airfields and supported the successful landing, after which "Harrison" arrived Port Purvis on Florida Island in the Solomons on 11 May for a month of local exercises and patrols.