In 1973 "Arethusa" began her modernisation which included the removal of her one twin 4.5-in gun, with the Ikara anti-submarine warfare missile system taking its place. The modernisation was completed in April 1977. In that same year, "Arethusa", like many Leanders, took part in the Royal Navy's Fleet Review in celebration of HM the Queen's Silver Jubilee. "Arethusa" was positioned between and and was part of the 3rd Frigate Squadron. Between 1978 and 1981 she was commanded by Kenneth Snow. In 1979, "Arethusa" deployed to the Far East and Pacific.