Presenting a unified approach to analysis tools, this book examines the integrated use of modeling and estimating in the analysis of structures. It provides readers with the knowledge required to know which calculations to perform, how to validate and interpret those calculations, and what the subsequent results mean. The text examines principles and techniques of mathematical modeling, including dimensional analysis, scaling, linearity, and balance and conservation laws. It also reviews basic structural models, discusses beam theory, the use of intuition, behavior of arches, modeling of tall buildings, and the use of Rayleigh quotients and Castigliano theorems.