It consisted initially of the City of Waterloo and the part of the City of Kitchener lying north of a line drawn from west to east along Highland Road West, Lawrence Avenue and Victoria Street.
In 2003, the Kitchener part of the riding was redefined to be the part of the city lying north of a line drawn from west to east along Highland Road West, Fischer Hallman Road and the Canadian National Railway situated north of Shadeland Crescent.
Following the 2011 Census and a Parliamentary decision to increase Federal electoral districts, Elections Canada tabled a proposal to replace the Kitchener-Waterloo district with a new Waterloo district and a reformed Kitchener Centre district. The new Waterloo electoral district will follow the boundaries of the City of Waterloo. The portion of the Kitchener-Waterloo district currently within the City of Kitchener will be assigned to a redefined Kitchener Centre district. If the proposal is approved by Parliament it is expected to take effect for the 2015 Federal election.
KW elected LiberalAndrew Telegdi in 1997, who had represented Waterloo since 1993. Telegdi enjoyed strong support among the German population in the region due to his stance on the Helmut Oberlander case. He was also known as a maverick, which made him unfavourable among some members of his own party, including Warren Kinsella for some stances he took against.
Telegdi was reelected by big margins in 2000 and 2004 along with the Liberals with a majority and minority government respectively. However in 2006 the Conservative Party of Canada led by Stephen Harper ousted the governing Liberals by winning a minority government. Despite the party's loss, Telegdi continued to enjoy immense support in his riding, fending off the Conservative challenger Ajmer Mandur by over 12000 votes.
In the 2008 federal election campaign, the riding was seen as one of the safest Liberal seats in the country after Telegdi's huge wins in previous elections. However, this time Telegdi faced a challenge from Conservative Peter Braid, a former staffer for Telegdi's predecessor, Progressive ConservativeWalter McLean, and a rookie politician, businessman, and father of two who campaigned on a theme of change and effective representation. Complacency from Telegdi's campaign along with hard work by Braid's campaign, his appeal to a wide range of voters including those in the suburbs, endorsement from popular local MPP Elizabeth Witmer, increased support for the local Green and NDP candidates, and a nation-wide surge for Harper's Conservatives combined to give Braid a narrow nail-biting victory of 73 votes on election night. The margin of victory was reduced to 48 votes following validation, which triggered an automatic recount. The result of the judicial recount was released on October 31, 2008, when it was announced that Braid was the victor by a mere 17 votes, the closest race in the country. Telegdi challenged Braid again in the 2011 elections, but after Braid retained his seat despite a more active Liberal campaign, Telegdi announced his retirement from politics.