This paper seeks to compare various models of desired, or ideal, vehicle lane-change trajectories or paths and to determine which is best based on selected criteria. Background information is presented covering the utility of lane-change maneuvers, lane-change terminology, and known desired open-loop trajectories. The performance of a vehicle may be assessed by measuring its deviation from an ideal path during simulated or actual limit lane-change maneuvers. Therefore, several techniques for assessing vehicle performance against an ideal trajectory are demonstrated. Similarly, in the present effort, performance indices such as integral penalty (cost) functions are used for assessing candidate lane-change trajectories. Therefore, ideal trajectory comparison is essentially treated as an optimization problem with prescribed continuity and boundary conditions, where a path's length, curvature, and rate of change of curvature are taken as its costs. The maximum constant velocity or critical speed is employed as an additional discriminator between the candidate paths. The results of side-by-side comparison of candidate ideal trajectories are presented and discussed.