This paper reports on the speech processing skills of a group of four year old children with specific speech difficulties and examines the impact of an additional language impairment on these skills. Forty seven children with speech difficulties were tested on two speech output measures and one speech input measure to assess the accuracy of their phonological representations. Their performance was compared to a matched control group n = 47 and analysed according to the presence/absence of an additional language impairment. It was found that children with both speech and language difficulties had poorer speech processing abilities compared to both the normal controls and the children with speech-only difficulties. The clinical implications of these findings are outlined.