It is generally agreed that the auditory perception skills of children with developmental language disorders are more limited than those of typically developing children. It is not easy to determine exactly how the capacity to discriminate and the capacity to pronounce phonemes influence each other in children with language disorders. For most authors, the inability to discriminate certain phonemes accurately causes a developmental delay in pronunciation, whereas others claim the influence is mutual. The aim of this study is to determine in which consonants perceptive difficulty is more likely to occur and in which cases there is a greater probability of difficulty when it comes to articulating them. The sample used in the study consisted of 86 children with a mean age of 4 years and 7 months. The phonological processes involved in simplifying speech were identified. Their errors were used as the basis on which to construct and apply a specific speech perception test. The relationship between the articulatory and perceptive skills of children with substitutive processes were analysed by means of two comparisons: first, in all the processes detected taken as a whole and, second, in the three most frequent substitutive processes. These analyses were carried out to determine whether the nature of the consonant implied a greater probability of perceptive difficulty. The findings provide information about a relation between the articulatory and perceptive skills, and about whether the nature of the consonant determines a higher probability of perceptive or articulatory difficulties. These results can be of value in the assessment, design and effectiveness of speech therapy programmes.