Poised as it is near the intersection of the east-west and north-south axes of the Mall, the NMAAHC will be the Washington Monument’s closest neighbor. Though exceptionally privileged, the site selected for the Museum is also exceptionally challenging: It is diagonally oriented to the vertical shaft of the Monument, and the ground level at its center lies some fourteen feet below that of the Mall. Our understanding of these conditions, together with the constraints imposed by required setbacks, led us to make two early decisions. The first was to raise the main entry level of the NMAAHC to the level of the Mall, so as to strengthen its presence there and reinforce its relationship to the family of museums arrayed along the Mall’s northern side. The second was to refrain from confronting the Monument with a monolithic building volume. Instead, we affirmed at roof level the largest square permitted within mandated setbacks, but then voided the building beneath it, so that the square form is seen not to define a volume but rather to frame a space. Next, we shaped a sinuous, curvilinear glass wall that further configures the space beneath the square roof and extends beyond it to the south in a gesture that responds to both the Monument and the Mall. Allowing the square, representing equality and permanence, to frame a dynamic space, representing journey and change, is the central idea of our design concept. As a further affirmation of the creativity fostered by equality, wood louvers contained within the three-story-high double-glazed wall will open and close throughout the day in a constant improvisational dance with the sun and sky.