Lead isotopes are sensitive indicators of crustal interaction in arc magmatism because of the large contrast in lead concentration between mantle-derived magmas and continental crust and the three independent decay paths in the U-Th-Pb system. Preserved within Wopmay Orogen (1.94 to 1.84 Ga) are the remnants of three magmatic arcs. The isotopic composition of lead in alkali feldspars separated from a diverse suite of samples from all three arcs fall in a relatively tight cluster with , , and , except for samples from the only plutonic suite within Wopmay Orogen observed to intrude Archean crust. Plutons intruding Archean crust have , , and . Lead isotopic compositions do not correlate with rock composition: both diorites and peraluminous granites have the same lead isotopic composition. This isotopic composition is elevated in relative to mantle values at 1870 Ma, suggesting that the lead isotopic signature of these magmas was dominated by a crustal reservoir. The extreme homogeneity of lead isotopes within Wopmay Orogen relative to those available in the Archean Slave Craton at 1.9 Ga preclude extensive involvement of Slave Craton in Wopmay magmatism, but it is consistent with involvement of only slightly older crust (ca. 2.0-2.4 Ga) whose presence has been inferred in the west. The involvement of only slightly older crustal material in arc magmatism may be considered an alternative to models invoking sediment subduction.