In patients who have sustained a severe acquired brain lesion, difficulties of verbal expression may appear in the earliest stages of recovery but they can also persist in the chronic phase, reducing the person’s ability to communicate adequately, live independently, participate in social or working life, and build and maintain relationships with family and friends. It is therefore essential to provide the patient with tools of Augmentative and Alternative Communication (AAC) to increase their possibilities for communicating: currently the market offers both low-tech and high-tech communication tools. The identification of suitable AAC tools is done by means of a multidisciplinary assessment including evaluation by a speech therapist of the communication and phasic skills and by an occupational therapist of the residual motor skills and wheelchair posture; specific training on the use of the tool is also needed. One of the future tools currently being developed for alternative communication are brain-computer interfaces.