This document discusses principles of design, including structural and decorative design. It outlines five key principles: proportion/scale, balance, rhythm, emphasis, and harmony/unity. Proportion examines relationships between objects and the golden ratio. Scale compares sizes. Balance can be symmetrical or asymmetrical. Rhythm uses repetition, gradation, transition, and radiation to move the eye. Emphasis indicates importance. Harmony unites all principles into a cohesive design. Examples illustrate each principle.