Patricio Aylwin Azócar OMCh (Latin American Spanish pronunciation: [paˈtɾisjo ˈelwin aˈsokaɾ] ^ⓘ; 26 November 1918 – 19 April 2016) was a Chilean politician, lawyer, author, professor and former senator who was the 30th president of Chile from 1990 to 1994. He was the first president to be elected after the end of Augusto Pinochet's military dictatorship following the 1988 Chilean presidential referendum, marking the Chilean transition to democracy in 1990. He was from the Christian Democratic Party.

Born in Viña del Mar, to British descent on his father's side, Alywin was an active politician since 1945. He was first elected Senator in 1965, and later became president of the Senate in 1971 under Salvador Allende's administration. After the 1973 coup, he led the Christian Democrat party on two separate occasions, and was elected president in 1989. His administration was defined by social and economic reforms, the latter of which led to a significant decrease in Chilean homeless population. Alywin was also a staunch supporter of the Chilean National Commission for Truth and Reconciliation, which sought to persecute those involved in human rights violations during the dictatorship.

Aylwin, the eldest of the five children of Miguel Aylwin and Laura Azócar, was born in Viña del Mar. An excellent student, he enrolled in the Law School of the University of Chile where he became a lawyer, with the highest distinction, in 1943. He served as professor of administrative law, first at the University of Chile (1946–1967) and also at the School of Law of the Pontifical Catholic University of Chile (1952–1960). He was also professor of civic education and political economy at the National Institute (1946–1963). His brother, Andrés, was also a politician.

On 29 September 1948, he was married to Leonor Oyarzún Ivanovic. They had five children (his daughter Mariana worked as a minister in subsequent governments) and 14 grandchildren (among them, telenovela and film actress Paz Bascuñán).

Aylwin's involvement in politics started in 1945, when he joined the Falange Nacional. Later he was elected president of the Falange in 1950–51. When that party became the Christian Democratic Party of Chile, he served seven terms as its president between 1958 and 1989.

In 1965 he was elected to the National Congress as a Senator. In 1971, he became the president of the Senate. During the government of Popular Unity, headed by Salvador Allende, he was also the president of his party, and he led the democratic opposition to Allende within and without Congress. He is credited, to some degree, with trying to find a peaceful solution to the country's political crisis. Distrusting Allende, Aylwin "demanded that the president appoint only military men to his cabinet as proof of his honest intent," which Allende did only partially, and Aylwin "apparently sided with pro-coup forces, believing that the military would restore democracy to the nation." He stated very plainly that between "a Marxist dictatorship and a dictatorship of our military, I would choose the second."

Aylwin was president of the Christian Democrats until 1976, and after the death of the party's leader, Eduardo Frei, in 1982, he led his party during the military dictatorship of Augusto Pinochet. Later he helped establish the Constitutional Studies Group of 24 to reunite the country's democratic sectors against the dictatorship. In 1979 he served as a spokesman in the group that opposed the plebiscite that approved a new constitution.

In 1982, Aylwin was elected vice president of the Christian Democrats. He was among the first to advocate acceptance of the Constitution as a reality in order to facilitate the return to democracy.