Previous research on the mental imagery abilities of synaesthetes has concentrated on visual and spatial imagery in synaesthetes with spatial forms (Price, 2009; 2010; Simner et al, 2008) and letter-colour synaesthesia (Spiller & Jansari,2008). Though Barnett and Newell (2008) asked synaesthetes of all types to fill out a questionnaire on visual imagery, most of their synaesthetes reported some form of linguistic-colour synaesthesia. We extend the investigation of mental imagery to a wider variety of synaesthesia types and a wider variety of sensory modalities using a questionnaire study and several tests of visual and auditory mental imagery ability. Our results indicate that, as a group, synaesthetes report making greater use of mental imagery than non-synaesthetes, in everyday activities. Furthermore, they self-report greater vividness of visual, auditory, tactile, and taste imagery than do non-synaesthetes. However, as a group the synaesthetes are not seen to do significantly better at the mental imagery tasks, in either the visual or auditory modalities. These results have important implications for our understanding of synaesthesia, in relation to potential fundamental differences in perceptual processing of synaesthetes and non-synaesthetes.