Designers use different symbols and configurations in their drawings to explore alternatives and to communicate with each other. For example, when thinking about spatial arrangements, they draw bubble diagrams; when thinking about natural lighting, they draw a sun symbol and light rays. Given the connection between drawings and thinking, one should be able infer design intentions from a drawing and ultimately use such inferences to program a computer to understand our drawings. This dissertation reports findings from empirical studies on drawings and explores the possibility of using the computer to
automatically infer designer's concerns from the drawings a designer makes.