Volunteering is considered first as a gift of time but the world of the gift does not generally fit into the framework of the economic calculation. Yet, volunteer work represents an important productive resource which is taken into account by voluntary associations and nonprofit institutions. This paper intends to estimate its money value. First, the difficulties raised by such an exercise are examined. They result from the lack of regularity and from the heterogeneity of surveys on volunteering. These difficulties also originate in the conceivable methods for attributing a money value to activities which, by nature, are extraneous to this type of measurement. These difficulties are not insurmountable provided statisticians agree about shar...