Japanese airspace capacity must expand in order to accommodate the increased air traffic expected in the near future. Efficient air congestion management is a promising approach for achieving this goal. Arrival management for inbound flights to Tokyo International Airport, the busiest airport in Japan, is considered to be the most demanding challenge for efficient air congestion management. In this paper, a concept of arrival management based on multiple aircraft trajectory optimization is proposed and examined using the actual flight track data. At first, free-flight trajectory optimization is applied to the inbound flights landing on one of the two runways to simulate the most efficient ideal flights. Next, time separation constraints at a merging point on the boundary of the terminal area are imposed in order to avoid conflicts among the aircraft in the terminal area. As a result of the optimization, optimal sequencing and flight time adjustments are generated. Benefits of the proposed concept are evaluated by comparing the optimal trajectories with the corresponding actual flight trajectories. Dynamic programming is used for the optimization of each flight trajectory and scheduling of the arrival times. The obtained results reveal that in addition to safe arrival time separation, trajectory optimization with arrival time assignment produces substantial benefits in terms of fuel consumption and flight time.