Fractal geometry is a product of fractal theory, a mathematical approach that describes the way space is filled by figures or objects. A fractal geometric figure is one that can be iteratively subdivided or grown in accordance with a series of rules. The overall fractal figure consists of parts that, when viewed at different levels of magnification, tend to resemble each other—if not be identical—and the figure occupies more space than its topological boundaries imply. While pure mathematical fractal figures can be infinite in their iterations, there are examples of fractal shapes with limited scales that can be found in architecture. This chapter provides a brief overview of the background of fractal theory and defines fractal geometry. It then examines the confusion regarding claims about fractal geometry in architecture before reviewing how architecture and fractal geometry can be combined through inspiration, application, or algorithmic generation.