The SIRGAS activities are coordinated by three working groups:
SIRGAS-WGI (Reference System) is committed to establish and maintain a regional densification of the ITRF. This objective was initially accomplished through two continental GPS campaigns in 1995 (SIRGAS95) and 2000 (SIRGAS2000), including 58 and 184 stations, respectively. Today, it is realized by aprox 500 continuously operating GNSS sites distributed over the Americas and the Caribbean (SIRGAS-CON network), which are weekly processed by the SIRGAS Processing and Combination Centres.
SIRGAS-WGII (SIRGAS at national level) is primarily responsible for defining the SIRGAS geodetic datum, which is given by the origin, orientation and scale of the ITRS, and the parameters of the GRS80 ellipsoid. At present, this working group is concentrated on promoting and supporting the adoption of SIRGAS in the American and Caribbean countries through national densifications of the continental network.
SIRGAS-WGIII (Vertical Datum) is dedicated to the definition and realization of a unified vertical reference system within a global frame. Its central purpose is to refer the geopotential numbers (or physical heights) in all Latin American countries to one and the same equipotential surface (W0), which must be globally defined. This includes also the transformation of the existing height datums into the new system.