Over the past 40 years, researchers have assumed that semantic interference effects in picture naming reflect competition among lexical candidates during retrieval. In this study, we examined the role of the familiarisation phase in which participants are shown the target pictures and required to rehearse the appropriate names before the picture–word interference (PWI) paradigm is performed. A previous study reported that omitting the familiarisation phase reversed the polarity of the semantic effect to facilitation. In two experiments using between- and within-participants design, respectively, we compared PWI performance with and without familiarisation while using matched stimuli and task parameters. Overall, the results showed the typical semantic interference effect following familiarisation. However, in both experiments, naming latencies did not differ significantly between related and unrelated distractors when familiarisation was omitted. The current findings suggest that familiarisation plays an important role in determining semantic interference in PWI, most likely via raising lexical competitor activation by priming links between targets and related concepts. We also discuss broader implications of our findings with respect to the replicability of reported semantic facilitation effects in PWI.