1985: Graduates from Central High.
1987: As a Penn State student, leads a six-day, 104-mile march from State College to Harrisburg to protest the university's investments with companies that do business with South Africa's apartheid government.
1992: Joins the Philadelphia District Attorney's Office after graduating from Georgetown University Law School with distinction as a Public Interest Law Scholar.
February 2003: Leaves the District Attorney's Office.
May 2005: Narrowly loses the Democratic primary for district attorney to his former boss, Lynne M. Abraham.
November 2005: Appointed as the Philadelphia's inspector general by Mayor John F. Street.
March 2009: A judge throws Williams off the ballot for district attorney in the May primary, ruling that he had failed to disclose all his sources of income as required by law. Williams is reinstated to the ballot on appeal two weeks later.
May 2009: Gets 42 percent of the vote in a five-candidate field to win the Democratic primary.
November 2009: With Abraham not running for reelection, Williams wins a decisive victory in the general election, becoming the first African American to be elected a district attorney in Pennsylvania.
June 2010: Begins a series of three-hour weekly walking tours of some of the city's most troubled neighborhoods.
September 2010: Receives an Eisenhower Fellowship to travel and study abroad, which he uses to study community-policing and crime-prevention programs in Australia and Ireland.
February 2011: A grand jury brings felony charges against Msgr. William Lynn for shielding sexually abusive priests in the late 1990s. Williams, a Catholic, says, "I love my church, but I detest the criminal behavior of priests who abuse, or allow the abuse, of children."
December 2011: Announces that he and his wife, Sonita, are divorcing.
April 2012: Philadelphia Gas Works files a lien for $578 against Williams for falling behind on his gas bill. Williams pays the bill the following month.
August 2012: A collection agency sues Williams for an outstanding Lowe's credit-card bill. A judgment of $1,826.56 is entered against Williams a month later.
June 2012: Msgr. Lynn is found guilty of one count of child endangerment. Williams says of other church officials that there is "no doubt there were many others who were culpable."
December 2012: Williams informs Police Commissioner Charles H. Ramsey that he will not prosecute drug cases from six narcotics officers, saying they had lost their credibility. Prosecutors would later throw out well over 100 cases.
November 2013: Easily wins reelection as district attorney.
December 2013: Lynn's conviction is overturned by a state appeals court. Williams appeals the decision a month later.
March 2014: Publishes an op-ed in the Inquirer that faults former state Attorney General Kathleen G. Kane for shutting down a sting operation that caught five Philadelphia Democrats accepting money or gifts, writing that she had besmirched the prosecutors who worked on the case. Two of those prosecutors, Frank G. Fina and Claude Thomas, later worked for Williams.
April 2014: Kane challenges Williams to reopen the sting case, which he accepts.
October 2014: Brings the first charges in the reopened sting cases, accusing former city Traffic Court Judge Thomasine Tynes of bribery for accepting a $2,000 Tiffany bracelet from the sting's undercover operative. Referring to taped conversations, Williams says the case is "press and play." Tynes would plead guilty to a conflict of interest count in November.
December 2014: Announces arrests of two more sting defendants, whom he says admitted their guilt when questioned by a grand jury.
March 2015: Charges three more state legislators in the sting case with bribery, conspiracy, bringing the total accused to six.
April 2015: Pennsylvania's Supreme Court reinstates Msgr. Lynn's conviction.
August 2015: The Inquirer reports that a grand jury had subpoenaed Williams' political campaign's financial records to determine if he misspent funds on personal expenses.
November 2015: Nine members of City Council sign a resolution urging Williams to fire three prosecutors who sent or received pornographic emails while working for the state Attorney General's Office. Williams reassigns them to lower-profile positions a month later.
January 2016: A campaign contributor says Williams had asked him to rent a house to his ex-wife at a below-market rate, an arrangement that drew the attention of the FBI.
August 2016: Belatedly reports receiving $160,050 in gifts from 2010 to 2015 that previously was omitted from mandatory statements of financial interests. The gifts included a free $45,000 roof repair on his home, cash gifts from friends, and airfare and lodging for vacations.
September 2016: Joe Khan, a former colleague of Williams' at the District Attorney's Office, becomes the first candidate to challenge Williams in the 2017 primary.
January 2017: The city's Board of Ethics fines Williams $62,000 for failure to report five sources of income and 89 gifts on city financial statements over six years. The fine is the largest penalty ever imposed by the board. The Inquirer and Daily News write editorials urging Williams to resign.
Feb. 10, 2017: Announces he will not seek reelection.
March 21, 2017: Federal authorities indict Williams on more than 21 counts, including wire fraud, honest services fraud, and bribery-related charges.
June 19, 2017: Williams' federal fraud trial starts with jury selection. Testimony begins the next day.
June 29, 2017: Williams accepted a mid-trial plea deal, pleading guilty to one count related to accepting a bribe. Under the terms of the plea agreement, he will resign immediately.