Publishers
- Institute for the Study of Labor (IZA)
- Institute for Voluntary Action Research (IVAR)
- Institute of Development Studies (IDS)
- Institute of Exercise and Sport Sciences at University of Copenhagen
- Institute of Fundraising
- Institute of International Education
- Institute of Management and Organizational Behaviour, Leibniz University Hanover
- Institute of Public Administration (IPA)
- Instituto Nacional de Estatistica (INE)
- Inter Ethnic Initiative for Human Rights Foundation
- Inter-American Development Bank (IDB)
- InterAction
- Interactive Applications Group, Inc
- International Center for Not-for-Profit Law (ICNL)
- International Child Development Initiatives (ICDI)
- International Committee on Fundraising Organizations (ICFO)
- International Council on Archives
- International Development Committee, House of Commons
- International Development Research Centre (IDRC) Canada
- International Disability and Development Consortium (IDDC)
- International Federation of Red Cross and Red Crescent Societies (IFRC)
- International Food Policy Research Institute (IFPRI)
- International Funders for Indigenous Peoples
- International Network on Strategic Philanthropy
- International NGO Training and Research Centre (INTRAC)
- International Non Governmental Organisations
- International Renaissance Foundation
- International Youth Foundation (IYF)
- Investing for Good
- Inyathelo: The South African Institute for Advancement
