A number of individual movements composed by Webern between 1909 and 1914 can be shown to be partly or wholly derived from chromatic aggregate arrays — linear, ordered constructs. These aggregate arrays are themselves derived from one of two compound interval cycles: c.c. 1:3, which ascends by semitones and minor thirds (the hexatonic scale), and c.c. 6:7, which ascends by tritones and perfect fifths. Webern's engagement with these aggregate arrays is described in terms of 'background' (the array as pre-compositional resource), 'deployment' (the selection of conjunct spans on the arrays), 'traversal' (deployment of contiguous or overlapping spans expressed in terms of direction) and 'articulation' (the transformation of the deployed spans into actual music). The presence of these arrays explains much of the 'data' posited by extant analyses of these movements; especially those that belong to the traditions of pitch-class set analysis, chromatic aggregation, or chromatic wedge formation. Webern's use of c.c. 1:3 and c.c. 6:7 is traced back as far as the 1905 String Quartet, where they operate as collections rather than arrays, and in a tonal context. Aggregate arrays in Op. 5 (1909) are found alongside hexatonic music akin to the Fortspinnung found in the 1905 Quartet (they are also found alongside decisively non array-based music). By 1911, Webern is deriving entire movements from these aggregate arrays (Op. 9/II, Op. 9/IV and Op. 10/IV). The end-point of this dissertation is a pair of movements from 1913–1914 (Op. 9/VI and Op. 11/II) where c.c. 6:7 and c.c. 1:3 aggregate arrays respectively interact with non-patterned arrays that are themselves secondary derivations of composed music. These non-patterned arrays, which are traversed in order, just like their patterned counterparts, are 'series' in all but name.