In this paper, the economic impact of non-standard activities on farms (NSAF) is analysed. After a discussion of NSAF, the export base theory is introduced as the analytical tool to assess its regional economic impact. The theory is applied to the Province of Zeeland in the Netherlands for the period 1998–2008. The first conclusion is that employment will increase by an estimated 193 full-time equivalents per year in this decade. This growth is mainly attributed to an expected rise in agri-tourism. The second overall conclusion is that the export base theory is a fruitful method to assess the regional economic effects of NSAF. The method may be applied to other regions as well.