Article omission is a well-documented phenomenon in early child speech. Interestingly, children differ in terms of how extensively they omit articles depending on their age and what language(s) they are exposed to. Different accounts have been proposed to account for this cross-linguistic variation. One of the most widely discussed models is the Nominal Mapping Parameter (NMP), originally proposed in Chierchia (1998), which relates variation in child language to the syntactic and semantic properties of noun phrases across languages (e.g. Chierchia, Guasti and Gualmini 1999, Guasti and Gavarro 2003, Guasti et al. 2004). Other influential accounts of determiner omission have been formulated in prosody-oriented research (e.g. Gerken 1991, 1994, Lleo 1998, 2001, Lleo and Demuth 1999, Roark and Demuth 2000, Demuth et al., in press). So far, no common agreement has been reached.This paper presents a study on article acquisition in English, German, Norwegian and Swedish, where article use is subject to similar syntactic and semantic conditions. Hence, the NMP predicts similar acquisition patterns. In terms of their metrical structure, noun phrases in these languages differ considerably. Accordingly, different acquisition patterns are expected.