This article is a presentation of the phenomenon of volunteerism. It will give the keys of a better understanding of the activity, and especially how it can be considered as a powerful spiritual practice which is used in venture operations. Step by step in this article, volunteerism will be shown in its all forms and all different way of application. Its range, scale and extent in the world will be presented. The interest of taking a serious consideration of it will be explained while listing the positive effects volunteerism can have on the individual, as physical as mental. The spiritual heritage of volunteerism will be also examined and put in perspective with the present situation of the International project of Auroville.