OBJECTIVE: To determine the therapeutic progress made by two children who underwent the Multiple Oppositions Model stimulated with the same target sounds. Presentation of clinical cases: this story was made up of two children with speech disorders, and a boy (S1) and a girl (S2), with ages between 4:2 and 4:11, respectively. Speech data were collected through the phonological assessment. For treatment, we used the Multiple Oppositions Model for 25 sessions with the same target sounds (/ s /, / z / and / Z / and his deputy [S]), all belonging to the class of fricatives. We analyzed the changes in the phonological inventory of each child, as well as the occurrence of phonological processes and post-treatment. It was observed that the guy who had more changes (S1) showed the largest purchases of phonemes in the phonological inventory. Regarding phonological processes, S1 showed the highest occurrence of cases in his speech, both pre-and post-therapy, making it difficult to speech intelligibility for the listener. The cases involving the class of the net were those with a higher percentage of occurrences, even after therapy. CONCLUSIONS: Multiple Oppositions Model allowed adequate progress in treating these children with speech disorders, providing an expansion in the phonological inventory and a decrease of occurrence of phonological processes in spite of differences in the evolution of each one.