Before becoming an MP, he was a Norwich City Councillor, serving as Group Leader 1989-1991. With the formation of the coalition government Lamb was appointed Chief Parliamentary and Political Adviser to Deputy Prime Minister Nick Clegg. In early 2012, he became Minister of State for Employment Relations and, later in the same year, moved to the post of Minister of State for Care and Support, a post he held until the 2015 election. Following Nick Clegg’s resignation, Lamb was a candidate for the leadership of the party, eventually losing to Tim Farron. Lamb served as Liberal Democrat spokesperson on Health 2015-17, while from July 2017 until his retirement in 2019, he was chair of the Science and Technology Select Committee.