Adults with intellectual impairments have a high prevalence of stammering. Characteristic speech and associated behaviours are also different in quality and more variable between individuals than those of the typical adult population. This paper describes a speech and language therapy group with two adults with intellectual impairments and atypical stammering. Sessions took place over 10 weeks, with a standard format using discussion about communication, speech modification and relaxation. Sessions were videotaped with participants' permission, and Talking Mats[TM] supported participants in explaining their responses to their stammering. The evidence suggests that both participants gained socially from attending the group. Analysis of video material and photographs of the mats demonstrated positive change in fluency for one participant immediately following the therapy block, but no change for the second participant. Clinical interventions for these clients need to incorporate theoretical and therapeutic approaches to intellectual impairment and consider adult and paediatric aspects of stammering.