Chiavi in Mano has a duration of roughly 20 minutes and is composed in a single continuous movement. Wyner described the composition of the piece in the score program notes, writing:

Much of the concerto was composed during the summer of 2004 at the American Academy in Rome in a secluded studio hidden within the Academy walls. While much of the composing took place far from home, the concerto comes out as a particularly "American" piece, shot through with vernacular elements. As in many of my compositions, simple, familiar musical ideas are the starting point. A shape, a melodic fragment, a rhythm, a chord, a texture, or a sonority may ignite the appetite for exploration. How such simple insignificant things can be altered, elaborated, extended, and combined becomes the exciting challenge of composition. I also want the finished work to breathe in a natural way, to progress spontaneously, organically, moving toward a transformation of the musical substance in ways unimaginable to me when I began the journey. Transformation is the goal, with the intention of achieving an altered state of perception and exposure that I am otherwise unable to achieve.^[3]

Instrumentation edit

The work is scored for an orchestra comprising two flutes, piccolo, two oboes, two clarinets, two bassoons, four horns, two trumpets, three trombones, tuba, timpani, percussion, and strings.^[3]