We use a randomized controlled trial and behavioral game to study the extent and determinants of income hiding in rural Vietnam. We focus on a training program that aims to promote gender equality and entrepreneurship among women in poverty who are engaged in running a small business. In one treatment arm, we allow husbands to participate in the training as well. While the impact of the training on income hiding is not significant at usual significance levels if only women are allowed to follow the training, we provide some evidence that the training invites women to hide income. Our study also suggests that allowing husbands to be present at the training intensifies this effect. We discuss several mechanisms that may explain these findings, including an increase in expected income and a decrease in information asymmetry between the spouses. (C) 2018 Published by Elsevier B.V.