R. Aid, L. Li, M. Ludkovski We consider competitive capacity investment for a duopoly of two distinct producers. The producers are exposed to stochastically uctuating costs and interact through aggregate supply. Capacity expansion is irreversible and modeled in terms of timing strategies characterized through threshold rules. Because the impact of changing costs on the producers is asymmetric, we are led to a nonzerosum timing game describing the transitions among the discrete investment stages. Read more [...]