Catharina Isabella "Ien" Dales (18 October 1931 – 10 January 1994) was a Dutch politician and social worker.

Born in Arnhem, she received a degree in education from the University of Amsterdam and worked in social services before her career in politics.

She became a member of the Labour Party (PvdA) in 1968 and was appointed State Secretary for Social Affairs and Employment in the Van Agt II cabinet, a position that she held between 1981 and 1982.

[1] Her father was Teunis Dales, who owned a business selling construction supplies and her mother was Wilhelmina Bertha Holstigen.

[4] She was appointed the director of social services for the municipality of Rotterdam by one of the aldermen, Elizabeth Schmitz, following the discovery of widespread fraud in the department, with the challenge of re-organising the system.

[4] After the 1989 general election, Dales was appointed the Minister of the Interior in the Lubbers III cabinet, taking office on 7 November 1989.