"Historic Shifts in Worldview: Sustainability challenges the predominant mechanicalparadigm rooted in 17th century science and calls forth a new ecological worldview. In this way,sustainability may be to the 21st century what humanism was to 15th century Europe and itshistoric movement toward mechanism. This study examines changes in attitudes, values, andbehavior indicative of the shift from the mechanical to the ecological worldview particular toarchitects and their practice. Studying these two worldviews offers a unique way to inform andreorient the process of design to achieve more sustainable versus less sustainable builtenvironments.Architects and Worldview: According to Horst Rittel (1930-1990), a pioneering theorist ofdesign and planning, "the course of designing depends decisively and at every step of reasoningon the worldview of the designer” (1963). Rittel questions the ability of "occupational styles thatwere refined in the first half of this [20th] century, based on Newtonian mechanistic physics..." tomeet contemporary social needs (1969). Carolyn Merchant, environmental historian and theorist,establishes the ecological and mechanical worldviews operational in today's Western Society andtheir underlying premises as presented in her work, The Death of Nature (Harper San Francisco,1980). The dichotomy between Merchant's mechanical worldview and ecological worldview issummarized by the diametric emphasis each places upon object (product), process, relationships,and context.Research Strategies: Two empirical research strategies were used to describe and analyzehow the worldview of the designer leads to sustainable or less sustainable built environments: 1)case comparison of known architects and their work; and 2) two pilot surveys of architecturalstudents and their rank order of design input/considerations. By the "constant comparative"method of data analysis (Glaser and Strauss), distinct patterns of similarities and differencesemerged from the data consistent with Merchant's worldview premises. SPCA (systemic andprospective sustainability analysis) was used to evaluate sustainable development achieved bydesign (Bell and Morse, 2003).Worldview and Sustainable Design Practice: Research findings inferred that a design approach that prioritizes process over object, relationships over autonomy, and context dependence increased the possibility of a sustainable outcome. Alternatively, the reverse,indicative of the mechanical approach and traditional design practice, inferred a tendency towardsless sustainable outcomes. The shift from the mechanistic "cognitive and occupational styles"(Rittel) towards sustainability and the new ecological worldview necessitates a revolutionarychange in how architectural design is practiced and taught."