This paper examines how uncertainty and credit constraints affect the cyclical composition of investment and thereby volatility and growth. We develop a model where firms engage in two types of investment: a short-term one; and a long-term one, which contributes more to productivity growth. Because it takes longer to complete, long-term investment has a relatively less cyclical return; but it also has a higher liquidity risk. The first effect ensures that the share of long-term investment to total investment is countercyclical when financial markets are perfect; the second implies that this share may turn procyclical when firms face tight credit constraints.The contribution of the paper is thus to identify a novel propagation mechanism: through its effect on the cyclical composition of investment, tighter credit can lead to both higher volatility and lower mean growth. Evidence from a panel of countries provides support for the model's key predictions.JEL codes: E22, E32, O16, O30, O41, O57.