Koos Verdam

{{Short description|Dutch politician (1915–1998)}}

{{Expand language|topic=bio|langcode=nl|date=October 2024}}

{{Infobox officeholder

|honorific-prefix = His Excellency

|name = Koos Verdam

|image = Pieter Verdam (1977).jpg

|caption = Koos Verdam in (1977)

|office = Extraordinary Member
of the Council of State

|term_start = 1 March 1980

|term_end = 1 February 1985

|vicepresident = Marinus Ruppert (1980)
Willem Scholten (1980–1985)

|office1 = Queen's Commissioner of Utrecht

|term_start1 = 16 March 1970

|term_end1 = 1 February 1980

|monarch1 = Juliana

|predecessor1 = Constant van Lynden van Sandenburg

|successor1 = Pieter van Dijke

|office2 = Member of the Senate

|term_start2 = 23 May 1967

|term_end2 = 16 March 1970

|office3 = Minister of the Interior

|term_start3 = 5 September 1966

|term_end3 = 5 April 1967

|primeminister3 = Jo Cals (1966)
Jelle Zijlstra (1966–1967)

|predecessor3 = Ivo Samkalden (ad interim)

|successor3 = Henk Beernink

|birthname = Pieter Jacobus Verdam

|birth_date = {{Birth date|df=y|1915|01|15}}

|birth_place = Amsterdam, Netherlands

|death_date = {{Death date and age|df=y|1998|03|11|1915|01|15}}

|death_place = Bilthoven, Netherlands

|party = Christian Democratic Appeal
(from 1980)

|otherparty = Anti-Revolutionary Party
(until 1980)

|spouse = {{marriage|Jantina Boomsma|29 April 1943}}

|children = Louwrens Verdam (1947–2006)
Tjeerd Jan Verdam (1948–2013)
5 other children

|residence =

|alma_mater = Vrije Universiteit Amsterdam
(Bachelor of Laws, Master of Laws, Doctor of Philosophy)

|occupation = Politician · Jurist · Researcher · Academic administrator · Professor

|signature =

|website =

}}

Pieter Jacobus "Koos" Verdam (15 January 1915 – 11 March 1998) was a Dutch politician of the defunct Anti-Revolutionary Party (ARP) now merged into the Christian Democratic Appeal (CDA).

The reformed Verdam was a professor for Roman law and international civil law at the Vrije Universiteit Amsterdam and from 1959 to 1960 its Rector Magnificus. From 1966 to 1967 he was the Minister of the Interior and Kingdom Relations in the Zijlstra cabinet. In 1970 he became the Queen's Commissioner of Utrecht.