Seattle designated the Pioneer Square Preservation District, the city's first historic district, nearly fifty years ago. Over the past half century, the district has seen significant infrastructure improvements, a changing resident population, and an evolving mix of businesses. Although many buildings underwent interior alteration, the visible external character of the historic fabric has remained largely intact. The district's Preservation Board reviews a constant stream of small exterior restoration and rehabilitation projects, but it is the relatively few examples of new infill construction that have presented the most challenging questions as the board has had to balance the desire for new development and the activity it brings with the wish to protect historic character.
Although the Pioneer Square District ordinance, the Secretary of Interior's Standards, and rules developed by the board all offer guidance, every new design presents questions about the exact meaning of terms like "compatible" and "differentiated." Today, with Seattle's booming economy and growing population, more new projects of a larger scale are being proposed. As a result, the Pioneer Square Preservation District presents a singular case study demonstrating continuing efforts to protect the historic built environment while still allowing appropriate growth.