The Department of Internal Affairs traces its roots back to the Colonial Secretary's Office, which from the time New Zealand became a British colony, in 1840, was responsible for almost all central Government duties. The department was the first government department to be established in New Zealand, and it became the home for a diverse range of government functions providing services to New Zealanders and advice to Ministers of the Crown. Hence the title of Michael Bassett's 1997 history of the department: The Mother of All Departments.

Many of these responsibilities were lost as new departments and ministries were formed. The office's name was changed to the Department of Internal Affairs from 19 November 1907. Change has continued to the present day, as new roles and functions have come into the department and others have been transferred elsewhere.^[6]

The Department of Internal Affairs includes the Office of Ethnic Communities which provides information to ethnic communities and policy advice to the government, and the Local Government Commission, which makes decisions on the structure and representation requirements of local government. The department present activities also include the implementation of recent dog control and local government legislation.

The department has responsibility for supporting the community and voluntary sector through the Office for the Community and Voluntary Sector.

The Chief Executive of the Department of Internal Affairs is also the Government Chief Digital Officer (GCDO), with responsibility for developing and overseeing the government's ICT (Information, Communications and Technology) strategy and providing strategic advice on related matters. The department also includes the National Library of New Zealand (Te Puna Māturanga o Aotearoa) and Archives New Zealand (Te Rua Mahara o te Kāwanatanga). These two organisations were integrated into the department on 1 February 2011.^[7][8]

The department provides secretariat support for several entities including:

• The Gambling Commission
• The Local Government Commission
• Commissions of Inquiry and ad hoc bodies such as the Royal Commission of Inquiry on Historic Abuse in State Care and in the Care of Faith-based Institutions
• The Library and Information Advisory Commission, Ngā Kaiwhakamārama i ngā Kohikohinga Kōrero
• The Public Lending Right Advisory Group
• The Guardians Kaitiaki of the Alexander Turnbull Library
• The Archives Council
• The Film and Literature Board of Review
• The Confidential Listening and Assistance Service

The department serves 7 portfolios and 6 ministers. In addition, the department also has responsibilities to the Minister of Finance in relation to community trusts and to the Minister of Foreign Affairs in relation to the Peace and Disarmament Education Trust and the Pacific Development Conservation Trust.^[9]

An invitation to present commercial opportunities (IPCO) is a process designed by the department to invite the private sector to present ideas for commercial relationships with government in relation to services already built/created by the government agency. The commercial relationships can include a public-private partnership or other arrangement between the private sector and the government to further develop, fund, innovate, distribute, and ensure uptake and use of the services.^[10]

An IPCO is issued where a government is seeking options that provide it access to private sector specialised expertise, innovative ideas, and funding and the sharing of risk. Extending the reach of the services, while building on the benefits of established branding and related market penetration are also important.

An IPCO is not a procurement process for goods or services, and it does not signal whether any final decision has been made on any future procurement process or any other action will be taken by government. It is intended to enable government to gauge whether there are organisations interested in, and what options are available for, public-private partnerships or other commercial arrangements to use and/or further develop, fund, innovate, distribute, and ensure uptake and use of a government agency's services by the public, government agencies and the private sector.

The IPCO process was developed in August 2009 to assist with collecting information from the private sector to use in advising government on future development and funding options for particular services. The IPCO has been used for two electronic identity services the New Zealand Government has built for government use to provide identity dependent services online. The two services are called the igovt logon service and the igovt identity verification service (igovt services). Government directed the Department of Internal Affairs to invite the market to provide written responses about whether private sector organisations were interested in:

• using the igovt services if available to them, and
• entering into public-private partnerships or other arrangements for the further development, funding, innovation, distribution, and ensuring uptake and use of the igovt services.

• New Zealand Birth Certificate
• Censorship in New Zealand
• Gambling in New Zealand
• Five Nations Passport Group

• Bassett, Michael The Mother of All Departments (1997, Auckland University Press, Auckland) ISBN 1-86940-175-1

• Official website
• Local Government Commission
• Ministry of Civil Defence
• Office of Ethnic Affairs