This ambitious book offers new perspectives on the role of vegetal ornament in medieval church design. Focusing on an extensive series of foliate friezes articulating iconic French monuments, such as Cluny III, Amiens Cathedral, and Mont-Saint-Michel, it demonstrates that church builders strategically used organic motifs to integrate the interior and exterior of their structures, and to reinforce the connections and distinctions between the entirety of the sacred edifice and the profane world beyond its boundaries. Mailan S. Doquang shows that, contrary to widespread belief, monumental flora was not just an extravagant embellishment devoid of meaning and purpose, or an epiphenomenon, but a semantically charged, critical design component that inflected the stratified spaces of churches in myriad ways. The friezes encapsulated and promoted core aspects of the Christian faith for medieval beholders, evoking the viridity of the paradisiacal garden, Christ as the True Vine, the Eucharistic wine and ritual, and the golden vine of the Temple of Jerusalem, originally built by the wise King Solomon. By situating the proliferation of foliate friezes within the context of the Crusades, moreover, this study provides new insights into the networks of exchange between France, Byzantium, and the Levant, and contributes substantially to the “global turn” in the field of medieval art and architectural history.