Greek word order is determined to a large extent by information structure: discourse-related concepts such as topic, focus, and background play an important role. Grammatical relations, on the other hand, are indicated by case morphology rather than word order. However, even when information structure is taken into account, the surface linearization of words/constituents is not straightforward: sometimes the topic precedes the focus, sometimes it's the other way around. In the paper, I discuss some ways of identifying topics and foci, and suggest that the notion of contrast is needed to give a more comprehensive account of Greek word order. I argue that Greek clause structure consists of an S which may be dominated by functional projections. Topics may be realized within S if they are not contrastive. Foci (or at least some element of a focus domain) must be realized outside S.