For children with intellectual disabilities (ID), stimulation of their language and communication is often not a priority. Advancements in brain research provide guidelines for early interventions aimed at the stimulation of language and communication skills. In the present study, the effectiveness of an early language intervention which draws upon neurocognitive principles of language processing and language learning was assessed. Ten children participated in the intervention and 18 were followed for control purposes. The intervention group showed greater progress than the control group. The higher learning gains for the intervention group were mostly driven by the non-speaking children. However, the progress of the intervention children slowed down significantly following intervention. An early language intervention such as that studied here can accelerate the language development of children with ID. To maintain the effects, however, the intervention should be prolonged in several settings that focus on consecutive learning (e.g., day-care centres "and" schools). (Contains 4 figures and 2 tables.)