The idea of building a working group on the Neoproterozoic-Early Palaeozoic of SW-Gondwana was born during the “I. International Colloquium Vendian-Cambrian of W-Gondwana”, held in Montevideo in April-May 2001. Thereafter, contacts with other specialists were made and the “II. International Colloquium Vendian-Cambrian of W-Gondwana” was held in Montevideo one year later, with valuable support from UNESCO. During this meeting, a first draft of the project was formulated, and the main objectives were set. Finally, a meeting on the subject took place on the 9th July 2002, during the 16th International Sedimentological Congress held in Johannesburg. As a result, 48 researchers from 26 institutions located in 9 countries agreed to participate actively, providing a wide basis to achieve the goals of the present project. Moreover, the meetings allowed the participants to exchange ideas directly with each other and build an active working group. The group is already involved in the edition and production of a special issue of “Gondwana Research” dealing with the Vendian-Cambrian of W-Gondwana, to be published in October 2003.