He served as leader of the National Party of Australia[a] from 1971 to 1984 and was the second and longest-serving deputy prime minister, holding the position under John Gorton (1971), William McMahon (1971–1972) and Malcolm Fraser (1975–1983).

[7] The Menzies government had not yet established a clear policy for Canberra's future, and Anthony stated that the city was not yet ready for self-governance.

At Narrogin in August 1966, Anthony relayed to several rural communities that drought would probably soon sweep the region, and that he was prepared to take precautions to prevent as many negative effects as possible.

[12] Controversially, in May 1968, Anthony initiated a payout of $21 million to offset the devaluation of the British Pound by Prime Minister Harold Wilson; the currencies were not yet independent of each other.

[14] Anthony worked with Prime Minister John Gorton to try to create as many economically viable options as possible to deal with the “wheat crisis”.

[15] When China stopped importing Australian wheat in 1971, Anthony advised against communication with the country, saying it could be “politically and commercially dangerous".

[6] Anthony was made a member of the Privy Council of the United Kingdom by Queen Elizabeth II on 23 June 1971.

When McMahon announced the 1972 election, he left Anthony in the dark and he was unaware of the date on which it would take place and the campaign techniques the coalition would use.

Despite that, the Country Party voted with the Labor government on some bills, for example the 1973 expansion of state aid to under-privileged schools.

[21] At first, Anthony did not support Snedden's or Fraser's decisions to block parliamentary supply from the Labor Party, beginning in October 1975, though he was soon convinced otherwise.

[24] In 1976, during his second term as Deputy Prime Minister, Anthony began a strong import and export relationship with Japan, particularly over oil.

[25] Anthony supported the mining and export of Australian uranium, and believed it would be an essential part of the future economy.

[27] While Acting Prime Minister in July 1979, he threatened to shut down an industrial strike in Western Australia, stating the issue had to be resolved.

The Labor Party was strongly opposed to this action and called his power as Acting Prime Minister into question.