After the 2008 general election the National Party formed a minority government with three confidence and supply partners. Despite his high list placing, Williamson was not selected for cabinet due in part to a series of gaffes during the election campaign relating to the party's policy on road tolls. He was given ministerial responsibilities outside of cabinet for Customs, Building and Construction, Statistics and Small Business. One of the major matters under his governance was the ongoing leaky homes crisis, which he noted as having the government "stumped" due to its enormity.