The analysis of labor supply under risk has a long history dating back to Hicks (The theory of wages, St. Martin's Press, New York, 2003) and Knight (Risk, uncertainty and profit, Kelly, New York, 1964). In the 1980s more technical papers investigated the impact of stochastic non-labor income and/or wage rate upon labor supply. In this paper, we show that the effect of a mean-preserving increase in risk in wage rate or non-labor income on labor supply is best understood as a special case of an Nth degree risk increase (as defined by Ekern (Econ Lett 6:329-333, 1980)) and the conditions for signing the effect of a higher-order risk increase in wage rate or non-labor income on labor supply are analogous to those for signing the effect of a simple non-stochastic decrease in wage rate or non-labor income. We thus extend, and provide new and more intuitive interpretations for, related earlier results. © Springer-Verlag 2010.