This paper presents findings from a study on the use of sign supported Norwegian (SSN) in two individuals with Cri du chat syndrome (CCS). The study gives a first account of some selected aspects of production and intelligibility of SSN in CCS. Possible deviance in manual parameters, in particular inter- and/or intra-subject variation in the use of handshape is investigated. Second, the question is addressed to what extent the isolated signs and isolated speech are intelligible and to what extent the combination of signs and speech in SSN contributes to a better intelligibility compared to each part in isolation. Results showed inter-subject variation, as well as individual consistency of deviancy in phonetic handshape parameters. Both participants were slightly more intelligible in their sign articulation when signs and speech production were analyzed separately. Importantly, intelligibility was greatly increased when signs and speech were combined. This emphasizes the importance of SSN for facilitating communication in children with CCS.