Commodities, ranging from natural gas to memory chips, can be procured both by trading on the date in spot
markets and in advance in forward markets. Transaction costs, such as brokerage fees, are typically higher in
spot markets than in forward markets. Moreover, the forecast of a ¯rm's commodity requirement (demand)
for a given future date typically changes in an uncertain fashion over time. Thus, although the dynamics
of forward and spot prices are notoriously uncertain, firms that procure commodities face the dilemma of
choosing between early and possibly less expensive commitments with residual demand uncertainty and late
and possibly more expensive sourcing of the exact amount needed. We investigate this issue by developing
and analyzing a model of commodity procurement for a single future date. Our model generalizes models
available in the real options and operations management literature, by simultaneously considering correlated
demand forecast and forward price updates in a setting characterized by multiple forward transactions
and a single spot transaction. We derive the structure of the optimal procurement policy and discuss its
computation in cases of practical interest. In a numerical study, based on applying our model to natural
gas data, we offer managerial insights on the effects that demand forecast and forward price updates, both
in isolation and combined, have on the value of a firm's procurement policy. We also assess the sensitivities
of these effects to parameters of interest and the potential managerial relevance of the combined effect. Our
model and results have significance beyond the specific application.