Overall, word order research has been shaped by three major, sometimes overlapping but not always interrelated, approaches to language analysis each of which focuses on a different dimension of linearization issues: word order as a syntactic phenomenon, as an expression of pragmatic relations in discourse, and as a representational issue in linguistic theory. In addition, word order phenomena have always attracted attention of historical linguists, as a specific area within the study of language change and variation. One area in linearization research that is only beginning to emerge is the study of word order in child language acquisition. Among the first proponents of a systematic study of the discourse-functional basis of word order variation are Prague School linguists, a tradition associated with two fundamental notions: communicative dynamism and the theme-rheme articulation. As to the current state of our understanding of the relationship between word order, information structure, and the cognitive principles that may motivate the interaction between the two, it can be stated that at the most general level, word order patterning can be motivated by grammatical, pragmatic, or cognitive principles — typically by a combination of these. In addition, even within a single layer of motivations, there may be several a priori equally justifiable principles that need not work in unison, but instead, present speakers with multiple options in selecting specific subsets of principles as the dominant ones.