This paper explores the effects of husbands' commuting time on their wives' labour market participation and on family time allocation. We develop a unitary family model of labour supply, which includes commuting times and household production. In a pure leisure model longer commuting time for husbands increases their wives' labour market participation and reduces their own working hours. However, a model that includes household production might determine the exact opposite result. We then examine the sign of these effects by using data from the German Socio-Economic Panel from 1997 to 2010. Employer-induced changes in home to work distances allow us to deal with endogeneity of commuting times. We find that a 1% increase in a husband's commuting distance reduces his wife's probability of participating in the labour force by 1.7 percentage points, 2% over the mean. Moreover, it increases his working hours by 0.2 hours per week. The average effect masks substantial heterogeneity: lower participation rates are concentrated in couples with children and where the husband has higher levels of education.