Over the past three decades, statistical approaches have been successfully used to explain how young language learners discriminate the sounds of their mother tongue(s), perceive and acquire linguistic categories (e.g. phonemes), and eventually develop their mental lexicon. In brief, input statistics, i.e. the relative frequency of the linguistic units that children are exposed to (e.g. phones, syllable types), appear to provide excellent predictors in the areas of infant speech perception and processing. This research offers useful insight into both the nature of the linguistic input that infants attend to and how they sort out the evidence from that input (see Gerken 2002 for a recent overview). Building on this success, a number of linguists have recently proposed statistical explanations for patterns of phonological productions that were traditionally accounted for through typological universals, representational complexity, grammatical constraints and constraint rankings, or lower-level perceptual and articulatory factors. For example, Levelt, Schiller and Levelt (1999/2000) have proposed, based on longitudinal data on the acquisition of Dutch, that the order of acquisition of syllable types (e.g. CV, CVC, CCV) can be predicted through the relative frequency of occurrence of these syllable types in the ambient language. Following a similar approach, Demuth and Johnson (2003) have proposed that a pattern of syllable truncation resulting in CV forms attested in a learner of French was triggered by the high frequency of the CV syllable type in this language. However, important questions need to be addressed before one can conclude that statistical approaches, or any mono-dimensional approach based on a single source of explanation, truly offer strong predictions for developmental production patterns. For example, one must wonder whether input statistics, which are mediated through the perceptual system and computed at the cognitive level, can have such an impact on production, given that production, itself influenced by the nature of phonological representations, (2009) François Pellegrino, Egidio Marsico, Ioana Chitoran & Christophe Coupé (eds.), Approaches to Phonological Complexity, 329-351. Berlin: Mouton de Gruyter.