This article reports an eye-tracking experiment with 2,500 polymorphemic Dutch compounds presented in isolation for visual lexical decision while readers' eye movements were registered. The authors found evidence that both full forms of compounds ("dishwasher") and their constituent morphemes (e.g., "dish," "washer," "er") and morphological families of constituents (sets of compounds with a shared constituent) played a role in compound processing. They observed simultaneous effects of compound frequency, left constituent frequency, and family size early (i.e., before the whole compound has been scanned) and also observed effects of right constituent frequency and family size that emerged after the compound frequency effect. The temporal order of these and other observed effects goes against assumptions of many models of lexical processing. The authors propose specifications for a new multiple-route model of polymorphemic compound processing that is based on time-locked, parallel, and interactive use of all morphological cues as soon as they become even partly available to the visual uptake system. (Contains 2 figures, 10 tables, and 7 footnotes.)