The Spanish Language Institute is organized under the laws of the Republic of Costa Rica as a non-profit organization whose legal title is "La Asociación del Instituto de Lengua Española." The Board of Directors and an Administrative Auditor are elected at the annual General Assembly. At the present time the Association enjoys the representation of the following groups among its members:
| Association of Baptists for World Evangelism | Methodist Church in Costa Rica |
| Baptist Church in Costa Rica | Mission Aviation Fellowship |
| Calvary International | Presbyterian Church in U.S. |
| Campus Crusade for Christ | Roblealto Child Care Association |
| Christian and Missionary Alliance | Salvation Army |
| Christian Reformed Church | Southern Baptist Convention |
| Clínica Bíblica | Spanish Language Institute |
| ESEPA Seminary | The Paul Mission |
| FEDEMEC (Evangelical Missionary Federation of Costa Rica) | UNELA (Evangelical University of the Americas |
| International Teams | United Bible Societies |
| Korean Church in Costa Rica | |
| Latin American Mission |