Response onset latencies for sentences that start with a conjoined noun phrase are typically longer than for sentences starting with a simple noun phrase. This suggests that advance planning has phrasal scope, which may or may not be lexically driven. All previous studies have involved spoken production, leaving open the possibility that effects are, in part, modality-specific. In 3 image-description experiments (Ns = 32) subjects produced sentences with conjoined (e.g., "Peter and the hat") and simple initial noun phrases (e.g., "Peter") in both speech and writing. Production onset latencies and participants' eye movements were recorded. Ease of lexical retrieval of sentences' second noun was assessed by manipulating codability (Experiment 1) and by gaze-contingent name priming (Experiments 2 and 3). Findings confirmed a modality-independent phrasal scope for advance planning but did not support obligatory lexical retrieval beyond the sentence-initial noun. This research represents the first direct experimental comparison of sentence planning in speech and writing.