[8] He went to school at Francis Douglas Memorial College, before enrolling at Massey University, applying to study veterinary science.

[9][10] With business partners, he built up RadioWorks over the next seventeen years, both organically and by acquisition, to a network of 22 radio stations and 650 staff.

He retired as Managing Director of RadioWorks in April 2001, when CanWest purchased it, Joyce receiving $6 million for the sale.

[23] Joyce was also appointed to the Office of Minister for Tertiary Education, Skills and Employment[24] replacing Anne Tolley, effective 27 January 2010.

In May 2013, he signed a deal with casino Skycity Auckland, allowing it to install an additional 230 pokie machines and 40 new gambling tables, in exchange for building a $402 million convention centre.

[31] During the lead-up to the 2017 general election, Joyce alleged that there was an NZ$11 billion hole in the opposition Labour Party's fiscal plan.

[31] However, on 6 March 2018, Joyce announced he would resign from Parliament, reportedly after not being offered the Finance portfolio under new National leader Simon Bridges, who had replaced Bill English.

According to political scientist Bryce Edwards, Joyce maintains close ties with the National Party and provided advice in the area of policy development.

[5] In June 2023, Radio New Zealand (RNZ) reported that the University of Waikato had paid nearly NZ$1 million in consultancy fees to Joyce Advisory.

[38][5] In July 2023, National pledged to establish a third medical school at Waikato University while campaigning for the 2023 New Zealand general election.

[39][40] Waikato University then hired Joyce's former press secretary and political advisor Anna Lillis to promote the school.

[7][5] In early May 2024, the Auditor-General John Ryan criticised Waikato University for not engaging in a competitive procurement process when contracting the services of Joyce Advisory.