This paper presents a downtown parking model that integrates traffic congestion and saturated on-street parking. We assume that the stock of cars cruising for parking adds to traffic congestion. Two major results come out from the model, one of which is robust. The robust one is that, whether or not the amount of on-street parking is optimal, it is efficient to raise the on-street parking fee to the point where cruising for parking is eliminated without parking becoming unsaturated. The other is that, if the parking fee is fixed at a sub-optimal level, it is second-best optimal to increase the amount of curbside allocated to parking until cruising for parking is eliminated without parking becoming unsaturated.