| European Chemical Substances Information System | Academic & Science |
| Elementary Student Information System | Academic & Science |
| Electronic Standby Instrument Systems | Academic & Science |
| Elementary Student Information Systems | Academic & Science |
| Electronic Student Information System | Academic & Science |
| Element Structure Information Set | Academic & Science |
| Enhanced Student Information System | Academic & Science |
| Ecological Site Information System | Academic & Science |
| Engineering Shared Infrastructure Services | Academic & Science |
| Earth Science Information System | Academic & Science |
| Exigon Sales Intelligence System | Business |
| Executive Search Information Services | Business |
| European Chemical Substances Information System (uk) | Chemistry |
| Education and School Improvement Service | Community |
| Economics of Staying In School | Community |
| Education Support and Inspection Service | Community |
| End System to Intermediate System | Computing |
| Executive Security Information System | General |
| Entrepreneurship Strategy and Information Systems | General |
| Earths Stratosphere Imaging System | General |
| Emergency Services Interactive Systems | General |
| Explicitly Simple intelligent Systems | General |
| Enhanced Status Information System | General |
| EUV Snapshot Imaging Spectrograph | General |
| European Survey of Information Society | General |
| Electronic Service Information System | General |
| European Space Information System | Governmental |
| Electronic Standby Instrument System | Governmental |
| Executive Search Information System | Governmental |
| Energy Standards Information System | Governmental |
| Elective Surgery Information System | Medical |
| European Standardised Information Sheet | Regional |
| European Structural Integrity Society | Regional |
| European Stress Information Service | Regional |
| European Standardized Information Sheet | Regional |
| Electronic Securities and Information System | Stock Exchange |
