Who makes the very first estimate of an aircraft's Maximum Takeoff Weight: The configuration designer, the aerodynamic performance engineer, or the weight engineer? At the point of conception of a new aircraft, before the first 3-view drawing is created, an estimate of the Maximum Takeoff Weight (MTOW) must be made. Other members of the team may be qualified to make this estimate, but I propose that the weight engineer can do an excellent job of estimating the initial MTOW. At a minimum, the weight engineer should contribute his expertise to the solution of this problem. This paper presents a method for estimating the initial MTOW. Additionally, it provides an improved way of evaluating the weight efficiency of aircraft that is far more rational than comparing the ratio of empty weight to gross weight. Quick checks of more detailed analyses and first order competitive assessments can also be performed with this method. Finally, the method is applied to the estimation of weight growth factors. The coefficients used herein are applicable to transport aircraft, but this basic approach could be applied to other vehicles.