This exam and study guide tests—and fosters—ownership of concepts in building systems, with an emphasis on the content stressed in the Architect Registration Examination (A.R.E.) Building Systems component. It is designed as a study tool, learning exercise, and confidence-builder. Questions are not reading comprehension devices that follow lessons, but rather opportunities to introduce a topic. Your time is valuable so this study guide does not treat all content that might appear on the exam equally. Rather it weights content by (1) its importance in the A.R.E. exam, and (2) its usefulness to the career of an architect. It further weights the content based on its “yield.” In other words, memorizing the entire plumbing code will certainly help you on the A.R.E. exam, but it is certainly not the most efficient means of studying for it.