When the Liberals came to office in 1949, Holt became a senior figure in the new government. As Minister for Immigration (1949–1956), he expanded the post-war immigration scheme and relaxed the White Australia policy for the first time. He was also influential as Minister for Labour and National Service (1949–1958), where he handled several industrial relations disputes. Holt was elected deputy leader of the Liberal Party in 1956, and after the 1958 election replaced Arthur Fadden as Treasurer. He oversaw the creation of the Reserve Bank of Australia and the decimal Australian dollar, but was blamed for a credit crunch that almost cost the Coalition the 1961 election. However, the economy soon rebounded and Holt retained his place as Menzies' heir apparent.