Opportunities to compare the written words of a designer with the products of their design process are rare. In the case of nineteenth-century architect and designer, A. W. N. Pugin such an opportunity exists. Augustus Welby Northmore Pugin (1812–1852) was an important figure in the English Gothic Revival movement. He was not only a designer but a writer who zealously preached his design principles. The breadth of Pugin's design work is astonishing given the brevity of his career. He not only designed buildings of various types, he also designed the finishes and furnishings found within. While Pugin is primarily remembered as an architect, he was also a gifted interior designer. Like Frank Lloyd Wright and others who came after him, Pugin's work embodied a holistic approach to design. For Pugin a structure, its interior spaces, furnishings, and decorative objects were to be part of a cohesive whole, to function physically and visually together. As a writer he created beautifully illustrated pattern books in which the Gothic style was featured. Books were also published that outlined his design principles. It is in those books that we find his rules for “proper” and “moral” architecture and interior spaces based on the Gothic design style. Rooted in Roman Catholic symbolism and ritual, the Gothic style seemed to Pugin to represent a moral fortitude that Classical design could not. Pugin associated pagan worship practices with Classical design and therefore believed that the only “true” design principles to follow where those related to the Gothic style of architecture. Pugin's major design principles were published in four books, Contrasts, True Principles, Present State and An Apology. The current study examines the principles found in An Apology and compares them with design work for a project of great significance in Pugin's life. St. Augustine's Church in Ramsgate, England was built with Pugin's own funds on his land next to the family home on a cliff overlooking the sea. As both client and designer Pugin followed his principles closely as descriptions of the interior spaces, furnishings, and decorative objects reveal. Comparing Pugin's written principles with the details of the spatial plan, ecclesiastical objects, and fittings within the church offers a glimpse of his creative process. Today, St. Augustine's Church stands as a manifestation of Pugin's written principles.