The membership was set by the 2007 Ontario general election on October 10, 2007.

It was controlled by a Liberal Party majority under Premier Dalton McGuinty.

It was initially led by John Tory but the leadership changed in 2009 when the PCs elected Tim Hudak as their new leader.

The third party was the New Democrats led by Howard Hampton until they chose Andrea Horwath as their leader in 2009.

The second, select committees, are struck usually by a Motion or an Order of the House to consider a specific Bill or issue which would otherwise monopolize the time of the standing committees.