The civil engineering and architectural communities are highly focused, these days, on designing buildings that maximize utilization of energy available from natural resources. This dissertation presents a quantitative study of the effect of high-rise office building morphology on energy and structural performances for the major climates. The parameters of the building morphologies are varied—the building footprint shape, the placement of the structural core/walls, and the building orientation. The energy analysis is performed using Autodesk Ecotect Analysis 2011; while using SAP2000 for the structure analysis and design. The key observations are: (1) the building morphology has a significant effect on the annual energy consumption, (2) placement of the structural core/walls in the east and west sides significantly improve the energy performance, (3) the tradeoff in the cost of placing the structural core/walls to maximize operating energy efficiency is too great, (4) for built to code buildings the energy demand may be considered marginally sensitive to changes in aspect ratio, and (5) high quality thermal properties of code-built envelope systems offer more flexibility to designers with regard to the building site planning without creating negative impacts on total energy demand.