The current thesis investigates the link between gestures and metaphor. In Chapter 3, we investigated whether left-hand gestures improve metaphor explanation compared to right-hand gestures or not gesturing at all. Additionally, we collected individual measurements for hemispheric involvement during speech production using the mouth asymmetry technique. We found a left-over-right hand gesturing advantage, which was higher for those with stronger right hemispheric involvement during speech production. This finding suggested that gestures’ self-oriented functions are hemisphere specific. In Chapter 4, we investigated whether left-hand gestures rather than taps trigger metaphorical language use. We found no such evidence, but we found that gestures compared to taps increased the number of words uttered, which in turn led to the use of more metaphors. This points towards gestures’ facilitative effect on speech production, but further research is needed to pin-point exactly what process is facilitated. In Chapter 5, we investigated whether gestures with a particular hand, when produced without speech, prime semantic categorisation of sentences (metaphorical and literal). We found no evidence for priming effects, and further research is needed to examine the effects that gestures, when produced alone might have on semantic processing. Finally, in Chapter 6 we found that producing content compared to function words, makes metaphor processing right hemisphere specific. This indicated that semantic processing is the key to the lateralisation of metaphor processing. The results validated the use of the mouth asymmetry technique as an indirect measurement of hemispheric involvement during speech production tasks.