How does prior context influence lexical-and discourse-level processing during real-time language comprehension? Experiment 1 examined whether the referential ambiguity introduced by a repeated, anaphoric expression had an immediate or delayed effect on lexical and discourse processing, using an eye-tracking while reading task. Eye-movements indicated facilitated recognition of repeated expressions, suggesting that prior context can rapidly influence lexical processing. However, context effects at the discourse level affected later processing, appearing in longer regression-path durations two words after the anaphor and in greater re-reading times of the antecedent expression. Experiments 2 and 3 explored the nature of this delay by examining the role of the preceding context in activating relevant representations. Off-line and on-line interpretations confirmed that relevant referents were activated following the critical context. Nevertheless, their initial unavailability during comprehension suggests a robust temporal division between lexical-and discourse-level processing.