Camillo Sitte (1843-1903) was an Austrian architect and professor of industrial design; his most famous work, City Planning according to Artistic Principles (1893), had a major influence on urban planning theory worldwide.
Sitte drew his inspiration from an examination of the built form of cities across Europe, principally from Austria, Germany, Italy, France and the Low Countries. He sought to identify the elements that contributed to aesthetically pleasing urban environments, and was perhaps the first person to study the relationship between buildings, and the nature of the space that separates them, rather than the design of the buildings themselves. His work concentrated on the size, shape and orientation of city squares and plazas, and the design of streets; put very simply, the ideal to be aimed at was a sense of 'enclosure'.
Sitte sought to guide planning in the twentieth century, and saw the principles he had identified as being applicable to modern conditions. However, modernist planners such as Le Corbusier who came to prominence barely two decades after Sitte's death saw him as hopelessly irrelevant to the modern world; in this, Sitte was not helped by adherents who adopted a self-conscious antiquarianism in their own designs, concentrating on the picturesque over the practical. Furthermore, they attempted to design in a pastiche medieval style, ignoring Sitte's own preferences for Baroque townscapes. However, although Sitte's theories were drawn from urban exemplars, he did have a major influence on the Garden City movement, very influential in the first half of the twentieth century, and in particular on Raymond Unwin who did much to popularise Sitte's ideas in the English-speaking world. Sitte's views, and work, also had a significant influence on the post-war Townscape movement of architects and planners in the United Kingdom.
George R. Collins & Christiane Crasemann Collins, Camillo Sitte: The Birth of Modern Planning (Dover Publications, Mineola, NY 2006)