In the forty years since the first iteration of Venice Architecture Biennale, the field of architecture has seen a remarkable change in the role played by exhibition-making. While architecture and display have long been intertwined practices, a rapid proliferation of large-scale perennial exhibitions--particularly in the twenty-first century--has resulted in the biennial / triennial becoming an integral part of our discipline, a new geography of itinerant display that has profoundly altered the contours of architectural thought. Between format, space, and content, what are the various agencies and effects of these events? Biennials / Triennials asks these questions and others of a range of curatorial agents--including After Belonging Agency, Beatriz Colomina and Mark Wigley, Sarah Herda, Adrian Lahoud, Ippolito Pestellini, and Andre Tavares--and visits crucial sites of recent exhibitions that reveal what is at stake in the newfound ubiquity of the architectural -ennial.