We study the consequences of a working time reduction (WTR) in a growth model with efficiency and an essential natural resource (natural capital) and in which technical progress cannot reduce the resource content of final production to zero. We show that if natural capital is scarce enough, a WTR increases the long-term levels of the hourly wage and employment. A numerical analysis of the transitory impacts of a WTR confirms that when natural capital is scarcer, a WTR increases employment more and the hourly wage less, with a less negative initial impact on output.