| Instituto Nacional de Ecología y Cambio Climático
|
| Integrated Ocean Observing System | Federal Partners
|
| Integrated Ocean Observing System | Regional Associations
|
| Integrated Water Resources Science and Services
|
| Interagency Task Force on Sea Level Change
|
| Intergovernmental Panel on Climate change (IPCC)
|
| Intermountain West DEWS
|
| International Centre for Integrated Mountain Development
|
| International City/County Management Association
|
| International Federation of Red Cross and Red Crescent Societies
|
| International Organization for Migration
|
| Internal Revenue Service
|
| International Trade Administration
|
| U.S. International Trade Commission
|
| International Union for Conservation of Nature
|
| International Water Institute
|
| Interstate Commission on the Potomac River Basin
|
| Inuit Circumpolar Council
|
| Inuit Knowledge Centre
|
| Inuit Tapiriit Kanatami
|
| Iowa Flood Center
|
| Iowa Institute of Hydraulics Research
|
| Iowa State University
|
| Iowa State University College of Agriculture and Life Sciences
|
| Iowa State University Department of Agronomy
|
