He farmed in Southland for two years before working at Imperial Chemical Industries New Zealand (ICI) as a sales representative and later as Manawatu-Wanganui field manager based in Palmerston North.
[1] While working with ICI, Lithgow met with farmers who were disgruntled with the declining state of the agricultural sector which he and they attributed to the Labour Government.
"[1] Lithgow helped to revive the National Party organisation in the Palmerston North electorate and was selected as its candidate for the 1975 general election.
[1] In his opening address to Parliament in July 1976, Lithgow spoke on the housing pressures Palmerston North was facing at the time, which he attributed to the growth of Massey University.
[6] On defeat, Lithgow promised he would continue to campaign on behalf of Palmerston North and intended to recontest the election again in 1981.