Little's term as Labour leader was characterised by low opinion polling results and punctuated by his resignation from the role less than two months before he was due to lead the party in the 2017 general election.

Little's decision was described as "selfless" and instrumental in Labour's success under new leader Jacinda Ardern; in the following six years he served as a senior minister and was regarded as a "safe pair of hands" across twelve ministerial portfolios.

[3] When he was 17, Little got his first job as a labourer digging the main cable trench for a new methanol plant in Waitara Valley as part of the "Think Big" project.

[5] In the 1980s Little studied law, philosophy and public policy at Victoria University of Wellington, where he became active in the campaign against New Zealand's student loan scheme.

[6] After graduating Little took a job as a lawyer with the Engineers' Union (a forerunner of the EPMU), with his work including Accident Compensation Corporation (ACC) and employment law issues.

[7] Together with Trevor Mallard, he launched attacks against ACC Minister Judith Collins, who eventually responded with issuing a defamation claim in May 2012.

[17] The Crimes (Corporate Manslaughter) Amendment Bill was drafted in the wake of the 2010 Pike River Mine disaster and the CTV Building collapse during the 2011 Christchurch earthquake.

At the time, Little stated the bill was needed because "the track record of prosecutions under the Health and Safety Act is that they tend to focus on lower level failures because getting the evidence and securing the conviction are easier, but personal responsibility for fatalities goes unchecked.

[24] Little announced his bid for the 2014 Labour Party leadership election on 9 October 2014 and was nominated by Poto Williams and Iain Lees-Galloway.

[29] Little largely focused on issues and concerns such as rising house prices in urban areas, a 'brain drain', unemployment and job security and the growing wage gap between baby boomers and millennials—the "Kiwi dream" narrative was particularly designed to engage young voters.

This appointment was made permanent in October 2015 after Jacinda Ardern (who had previously sought to be Robertson's deputy leader[31]) was reportedly offered the role but turned it down.

[33] For much of Little's leadership, key portfolios in the Little shadow Cabinet were held by King (health), Phil Twyford (housing), Chris Hipkins (education), Ardern (justice and children) and Carmel Sepuloni (social development).

[47] Following a negative evaluation by the Ministry of Justice, in March 2020, Little published a media release which claimed the AODTC was expensive to operate and needed modifications to "sustain reoffending gains over the long term".

[49][50] On 19 April 2018, Little entered the Pike River mine portal with victims' family representatives Anna Osborne and Sonya Rockhouse to demonstrate that a safe re-entry was possible.

[57] NZ First refused to back this proposal forcing Little to announce on 11 June 2018 that the coalition Government had abandoned the plan.

[61][62] In response, Little criticized Australia's deportation laws for lacking "humanitarian ideals" and described the removal of New Zealand citizens who identified as Australian residents as a human rights violation.

[63] In response, the Australian Minister for Home Affairs Peter Dutton defended his government's deportation policy and called on Little to reflect "a little more" on the Trans-Tasman relationship.

Little rejected Peters' call for a referendum, stating that the Government would seek the support of MPs from all parties to pass the legislation.

[71] On 22 July 2020, Little was appointed Minister for Workplace Relations and Safety following the resignation of Iain Lees-Galloway due to an affair with one of his staff members.

[75] On 20 July 2021, Little, in his capacity as Minister in charge of the Government Communications Security Bureau, confirmed that the spy agency had established links between Chinese state-sponsored actors known as "Advanced Persistent Threat 40" (APT40) and malicious cyber activity in New Zealand.

In addition, Little confirmed that New Zealand was joining other Western governments including the United States, United Kingdom, Australia and the European Union in condemning the Chinese Ministry of State Security and other Chinese state-sponsored actors for their involvement in the 2021 Microsoft Exchange Server data breach.

In response, the National Party's health spokesperson Shane Reti accused Little of denying that New Zealand's healthcare system was facing a crisis.

[80] In early July 2022, the Association of General Surgeons issued an open letter to Little stating that the staffing shortage was undermining the ability of doctors to deliver care to patients.

Prime Minister Chris Hipkins, who succeeded Jacinda Ardern earlier in the month, stated that Little had supported "any decision made about the portfolio" and added that he had full confidence in Little.

[83][84] Little also retained his ministerial portfolios for the GCSB, NZSIS, Public Service, Treaty of Waitangi negotiations and Lead Coordination Minister for the Government's Response to the Royal Commission's Report into the Terrorist Attack on the Christchurch Mosques.

[89] On the same day as his official resignation, he was granted retention of the title The Honourable, in recognition of his term as a member of the Executive Council.

[94] Little's support for AUKUS differed from the Labour Party, which has since 2024 expressed opposition to New Zealand's involvement in the security pact.