5 Pounds

The signature combinations on this series track a specific administrative transition at the Central Bank. T.K. Whitaker — better known as the architect of Ireland's 1958 Programme for Economic Expansion — served simultaneously as Secretary of the Department of Finance and, from 1969, as Governor of the Central Bank, which is why his name appears across multiple signature pairings spanning both roles. His presence on Irish currency during this period was unusually significant given his direct influence over the monetary and fiscal policies those notes underpinned.

The addition of a security thread to issues from January 1971 onward distinguishes the later printings from earlier examples of the same type — a detail that matters when attributing undated or lightly dated specimens within the P#65 series.