Translated from the Portuguese original. Read the original (Português)
Augmentative and Alternative Communication (AAC) brings together tools and strategies that complement or replace speech for people who have difficulty communicating. It ranges from gestures to picture boards and speech-generating apps on tablets. Contrary to what many assume, AAC does not delay or prevent speech — it gives a voice, reduces frustration, and can even support language development.
Augmentative and Alternative Communication (AAC) is the set of tools and strategies that complement (augmentative) or replace (alternative) speech for people with communication difficulties. The goal is to guarantee an effective way for the person to express themselves and be understood, in any setting.
What “augmentative” and “alternative” mean
The two words describe two roles these tools can play. When a person speaks a little but is not always understood, AAC is augmentative: it adds to speech and reinforces it. When speech is not yet functional or is not available, AAC is alternative: it becomes the main channel of communication. In practice, many people use a bit of both, depending on the situation and who they are talking to.
The key point is understanding that communicating is not just speaking. Pointing at a picture, handing over a card, touching a symbol on a tablet screen, or making a gesture are also legitimate and complete ways of saying what someone wants.
The types of AAC
AAC is usually organized into two broad groups: the kind that does not depend on any external material (unaided) and the kind that uses some physical or digital tool (aided). Explore each type:
Unaided AAC
Uses only the person's own body, with no external material at all: gestures, facial expressions, and signs. These are resources that are always available, which the person carries with them at all times — from pointing and waving to more structured sign systems.
Aided AAC — low technology
Relies on simple physical materials, with no electronics: pictures, communication boards (cards with symbols and words), and systems such as PECS, in which the person hands over picture cards to make requests and communicate.
Aided AAC — high technology
Uses electronic devices that produce speech: speech-generating devices (devices that “speak” when a symbol is touched) and speech apps on tablets. The person selects symbols or words and the device produces the message out loud.
The myth that gets in the way the most
Many families put off AAC for fear that it will make the child “too comfortable” and delay speech. That concern is understandable, but it does not hold up against the evidence.
An important myth to bustAAC does not delay or prevent speech. Research shows that it does not harm speech development and can even support it, in addition to reducing the frustration of not being able to make oneself understood. Giving someone a way to communicate does not take away anyone's drive to speak.
Presumption of competenceAAC starts from an ethical premise: it is assumed that the person has something to communicate. The problem is not a lack of something to say, but a lack of a means to say it. The system exists precisely to offer that means.
Who teaches how to use it: the communication partner
An AAC system does not work on its own. The people around the person — parents, teachers, therapists — also need to use it. This practice is called modeling or aided language stimulation: the adult speaks while pointing to the matching symbols, showing in practice how the tool is used to communicate.
- Just as a child learns to speak by hearing others speak, they learn to use AAC by seeing others use it.
- Speaking while pointing to the symbols teaches vocabulary, organizes ideas, and gives examples of how to combine messages.
- The system needs to be available and accessible at all times — not kept aside for “therapy moments.”
How a system is chosen
There is no single system that works for everyone. The choice and implementation of AAC are made by a team — including speech-language pathology and other professionals involved — on an individualized basis. It takes into account each person's skills, context, and needs, and the system is adjusted over time.
AAC is not “all or nothing”Unaided systems and low- and high-technology systems do not compete with each other. The same person may use gestures with their family, a board at school, and an app on a tablet — combining tools depending on the moment.
Test your understanding
Quick quiz
Three questions to reinforce the concept. You'll see the explanation right away.
Further reading
- Millar, D. C., Light, J. C., & Schlosser, R. W. (2006). “The Impact of Augmentative and Alternative Communication Intervention on the Speech Production of Individuals With Developmental Disabilities: A Research Review” (meta-analysis). Journal of Speech, Language, and Hearing Research (JSLHR).
- Romski, M., & Sevcik, R. A. (2005). “Augmentative Communication and Early Intervention: Myths and Realities”. Infants & Young Children.
- American Speech-Language-Hearing Association (ASHA). Augmentative and Alternative Communication (AAC).
This entry is educational and does not replace assessment, diagnosis or treatment by a qualified health professional. Every person is unique — for a specific case, seek individual guidance.