This paper examines the influence of risk aversion on the pricing policies of a market maker for securities. It is shown that a market maker's bid-ask spread can be decomposed into a portion for the known limit orders, a risk-neutral adjustment for expected market orders, and a risk adjustment for market order and inventory value uncertainty. It is demonstrated that a risk-averse market maker may set a smaller spread than a risk-neutral specialist. Finally, this paper demonstrates the pervasive role of inventory in affecting both the placement and size of the spread.

The work of Black and Scholes [2] and Merton [4] suggests that analysis of hedged positions in a continuous time random walk model yields powerful insights into the valuation of financial securities. The present paper extends this methodology in a straightforward fashion to foreign exchange transactions. By adopting the device of hedging in a secondary market for forward currency contracts against a long position in spot currency, a simple statement of boundary conditions for the forward position can be detailed. This allows a direct solution of the continuous time valuation problem that yields the interest rate parity theory.