Dr Pentti Arajärvi was born in Helsinki on 2 June 1948. He completed his Master of Laws at the University of Helsinki in 1972, his licentiate in 1996 and his doctorate in 2003.
Dr Arajärvi began his career at the Ministry of Education, where he served as referendary, senior secretary, counsellor of education and head project secretary in 1972-1984.
In 1984 he started work at the Finnish Parliament, where he was secretary of the Social Affairs and Health Committee and of the Economic Affairs Committee up to 1 March 2000, when Tarja Halonen's presidential term began. Since then he has been on a leave of absence. In 1986-1987 he was political secretary to the Minister of Education and in 1996-1997 he served as a rapporteur on income security legislation.
Dr Arajärvi held the position of head researcher at the Social Insurance Institution in 2000-2002, studying income security legislation in relation to constitutional rights, human rights and EU law. He was appointed acting professor of Social Law at the University of Joensuu in 2003-2006 and acting professor of Social and Educational Law in 2003-2011. In 2011 he was appointed acting professor of Social Law at the University of Helsinki. This is a part-time position. In 2003 he served as a rapporteur on income support, fees and taxation in adult education and training for the Ministry of Education; in 2006 a one-man committee on operational preconditions of nongovernmental organizations; and in 2008 a one-man committee on the project established by the Ministry of Interior to evaluate obstacles to immigrant employment and income trap.
Dr Arajärvi has actively participated in civic organizations in the fields of education, social welfare and sport. He has taken part in human rights organizations, the promotion of child psychiatry research and anti-drug work. He was a member of the City of Helsinki Education Committee in 1989-2000.
Dr Arajärvi has written three books on legislation in the education field and four other books on topics ranging from Europe and Finland to the welfare society. His doctoral dissertation was entitled "The flawlessness of income security legislation. Finnish legislation on income security in relation to the Constitution, with particular reference to constitutional rights, human rights and EU law". He has also published numerous articles in the fields of education, social welfare, and constitutional and human rights.
Dr Arajärvi is married to President Tarja Halonen and has one son. He enjoys hiking, camping and basketball and his special interests include literature, art and history. His civic activity focuses on welfare issues.