People often make important decisions based on information elicited from experts with uncertain preferences. We provide a theoretical rationale for the use of information markets in decision making tasks. Specifically, we show that markets for claims on decision-relevant variables can be efficient incentive schemes for eliciting information. Our model shows decision makers will subsidize liquidity in illiquid decision markets to gather valuable information. Our model also shows that the mere act of linking the decision to the market price will typically enhance liquidity in the market. Overall, our results highlight the potential for using information markets in diverse decision making tasks.