If you are a parent who has just learned that your child could benefit from augmentative communication, a caregiver supporting a loved one after a stroke, or a professional exploring AAC tools for the first time, this guide is for you. Communication is one of our most fundamental human needs, and augmentative and alternative communication (AAC) opens pathways to connection for millions of people around the world.
This comprehensive guide explains what AAC is, who benefits from it, the different types available, and how to take the first steps toward finding the right communication solution. Whether you are completely new to AAC or looking to deepen your understanding, you will find the information you need here.
What Is AAC?
Augmentative and Alternative Communication (AAC) refers to any method of communication that supplements or replaces speech for individuals who have difficulty with verbal communication. The term covers a broad range of tools and strategies, from simple gestures and picture boards to sophisticated speech-generating software on tablets and smartphones.
The word augmentative means adding to or enhancing someone's existing speech. Many AAC users do have some speech abilities, and AAC helps them communicate more effectively. The word alternative means providing a completely different way to communicate when speech is not possible.
According to the American Speech-Language-Hearing Association (ASHA), approximately 2 million people in the United States alone have significant communication difficulties that could benefit from AAC. Worldwide, the number is far larger, spanning every age group and many different conditions.
AAC does not replace speech or prevent speech from developing. Research consistently shows that AAC actually supports and encourages speech development in children and helps maintain communication abilities in adults with progressive conditions. It is a bridge, not a barrier.
Who Uses AAC?
AAC is used by a remarkably diverse group of people. There is no single profile of an AAC user. Some individuals use AAC from early childhood, while others begin using it later in life due to acquired conditions. Here are some of the most common groups who benefit from augmentative and alternative communication:
Children and Adults with Autism Spectrum Disorder
Many individuals on the autism spectrum have difficulty with verbal communication. Some are nonspeaking, while others have speech that is limited, inconsistent, or unreliable under stress. AAC provides a reliable, consistent method for expressing needs, feelings, thoughts, and preferences. Symbol-based AAC systems are particularly helpful for individuals who are strong visual learners, as they pair images with words to build language skills.
Stroke Survivors with Aphasia
Aphasia is a language disorder that frequently occurs after a stroke, affecting the ability to speak, understand language, read, and write. Approximately one-third of stroke survivors experience aphasia. AAC tools such as picture boards, text-to-speech apps, and phrase prediction software help individuals with aphasia continue communicating during recovery and beyond. Even if speech returns partially, AAC remains a valuable backup during moments of difficulty.
People Living with ALS (Amyotrophic Lateral Sclerosis)
ALS progressively weakens the muscles used for speech. As the condition advances, many people with ALS transition from natural speech to various forms of AAC. Early adoption of AAC, often starting with speech-generating apps on tablets, ensures that communication remains possible throughout the progression. Voice banking, where a person records their natural voice while still able to speak, allows their future AAC device to sound like them.
Individuals with Cerebral Palsy
Cerebral palsy can affect the motor control needed for speech production. Depending on the type and severity, individuals may have dysarthria (unclear speech) or anarthria (no speech). AAC systems with large touch targets, switch access, or eye-gaze technology allow effective communication regardless of physical limitations.
Children with Down Syndrome
Many children with Down syndrome have a significant gap between what they understand (receptive language) and what they can express verbally (expressive language). AAC bridges this gap, giving children a way to express the rich understanding they already possess while their verbal skills continue to develop.
People with Traumatic Brain Injury
Brain injuries can cause a range of communication difficulties depending on which areas of the brain are affected. AAC may be used temporarily during recovery or as a long-term communication support, helping individuals participate in rehabilitation, express their needs, and maintain social connections.
Individuals with Apraxia of Speech
Apraxia is a motor speech disorder where the brain has difficulty coordinating the muscle movements needed for speech. Individuals with apraxia know what they want to say but struggle to produce the words consistently. AAC provides a reliable communication backup while speech therapy works on improving verbal production.
Types of AAC
AAC systems are broadly categorized into two main types: unaided and aided. Within aided systems, there is a further distinction between low-tech, mid-tech, and high-tech solutions. Most AAC users benefit from a combination of approaches, using different tools in different situations.
Unaided AAC
Unaided AAC uses only the person's own body to communicate. No external tools or devices are needed. Examples include:
- Gestures and pointing: Using hand movements to indicate objects, directions, or concepts
- Facial expressions: Conveying emotions and responses through facial movements
- Sign language: Formal language systems like American Sign Language (ASL) or Makaton
- Body language: Using posture, movement, and physical proximity to communicate
- Vocalizations: Non-speech sounds that carry meaning, such as humming or specific vocal patterns
Unaided AAC is always available since it requires no equipment, making it an essential foundation for communication. However, it requires the communication partner to understand the signals, which can limit its effectiveness with unfamiliar people.
Low-Tech Aided AAC
Low-tech AAC uses physical tools that do not require batteries or electricity. These are often the first AAC tools introduced because they are affordable, portable, and easy to customize. Examples include:
- Picture Exchange Communication System (PECS): A structured system where the user selects and hands over picture cards to communicate
- Communication boards: Printed boards with symbols, pictures, or words organized by category
- Visual schedules: Sequences of images showing daily activities or steps in a routine
- Choice boards: Simple displays showing two or more options for the user to select from
- Communication books: Multi-page collections of symbols organized by topic, allowing for a large vocabulary
- Alphabet boards: Letter-by-letter spelling boards for literate users
Mid-Tech Aided AAC
Mid-tech AAC uses simple electronic devices, typically battery-powered, to produce speech output. These bridge the gap between low-tech and high-tech solutions:
- Single-message devices: Buttons that play a single recorded message when pressed (like a BIGmack)
- Sequential message devices: Record and play back a series of messages in order
- Multi-level devices: Simple devices with multiple buttons, each pre-recorded with a different message
High-Tech Aided AAC
High-tech AAC uses sophisticated electronic devices or software applications that generate speech from text or symbol selection. These offer the most extensive vocabulary and communication capabilities:
- Dedicated speech-generating devices (SGDs): Purpose-built communication devices like those from Tobii Dynavox or PRC-Saltillo
- AAC apps on tablets and smartphones: Software like SpeakAid, Proloquo2Go, TouchChat, and LAMP Words for Life
- Eye-gaze systems: Technology that tracks eye movements to allow selection of symbols or letters on a screen
- Head-tracking devices: Systems that follow head movements to control an on-screen cursor
Most AAC experts recommend a multi-modal approach, meaning an individual uses several types of AAC depending on the situation. Someone might use sign language at home with family, a communication board at school, and a speech-generating app for conversations with unfamiliar people. No single tool needs to do everything.
Comparing AAC Types at a Glance
| Type | Examples | Best For | Considerations |
|---|---|---|---|
| Unaided | Gestures, sign language, facial expressions | Quick, everyday interactions with familiar partners | Requires partner understanding; limited vocabulary with strangers |
| Low-Tech | PECS, communication boards, visual schedules | Starting AAC, young children, backup system | Affordable, no batteries; slower communication rate |
| Mid-Tech | Recorded message devices, simple buttons | Quick messages, social participation, early communicators | Limited vocabulary per device; needs re-recording to change |
| High-Tech | AAC apps, speech-generating devices, eye-gaze | Complex communication, large vocabulary, independence | Most expressive; requires charging, learning curve |
How to Choose the Right AAC System
Choosing the right AAC system is one of the most important decisions in the AAC journey. The best system depends on the individual's communication needs, physical abilities, cognitive skills, environment, and personal preferences. Here are the key factors to consider:
Communication Needs
Consider what the person needs to communicate about and with whom. Someone who needs to express basic wants and needs may start with a simple system, while someone who wants to have detailed conversations, tell stories, or participate in academic work needs a system with a large vocabulary and the ability to create novel sentences.
Physical Abilities
The person's motor skills significantly influence which AAC systems are appropriate. Consider whether they can point accurately with a finger, use hand signs, press buttons, or if they need alternative access methods like eye gaze or switches. Some AAC apps, like SpeakAid, offer flexible access options that can be adjusted as abilities change.
Cognitive and Language Level
The person's current understanding of language, ability to learn symbols, and literacy skills all influence the choice. Symbol-based systems work well for people who are pre-literate or have difficulty with written language. Text-based systems are appropriate for literate users. Many systems, including SpeakAid, offer both options.
Age and Development
For young children, AAC systems should be developmentally appropriate and grow with the child. A system that is too complex can be overwhelming, while one that is too simple can limit communication growth. Look for systems that can be easily expanded as skills develop.
Environment and Portability
Consider where the person communicates most often. A communication board might work well at a desk but is impractical while walking. A smartphone app offers portability that a large dedicated device cannot match. Think about noise levels, lighting conditions, and whether the system needs to work in multiple environments.
Budget
AAC systems range from free (printed communication boards, some apps) to several thousand dollars (dedicated devices with eye-gaze). AAC apps on existing smartphones and tablets offer a cost-effective middle ground. SpeakAid, for example, is free to download with a subscription for advanced features, making it accessible to families who cannot afford traditional AAC devices that can cost $150 to $300 or more for apps alone, and thousands for dedicated hardware.
A speech-language pathologist (SLP) experienced in AAC is the best resource for choosing and configuring an AAC system. They can assess the individual's needs, trial different options, and provide training. Many school districts, early intervention programs, and rehabilitation centers have SLPs who specialize in AAC.
Getting Started with AAC
Starting with AAC can feel overwhelming, but it does not need to be. Here is a practical step-by-step approach to beginning the AAC journey:
Step 1: Get a Professional Assessment
If possible, seek an evaluation from a speech-language pathologist (SLP) who has experience with AAC. They can assess the individual's communication strengths and needs, recommend appropriate systems, and create a plan for implementation. If you are in the United States, you can find SLPs through the ASHA ProFind directory. For children, contact your school district about AAC evaluation through special education services.
Step 2: Start with What You Have
You do not need to wait for the perfect system to begin AAC. Start with low-tech options like simple choice boards or printed pictures while exploring high-tech options. If you have an iPhone or iPad, you can download an AAC app like SpeakAid and begin exploring immediately. Starting early is more important than starting perfectly.
Step 3: Begin with Core Vocabulary
Core vocabulary refers to the small set of words that make up the majority of what we say. Words like "more," "stop," "help," "want," "go," "not," "I," "you," and "like" are used far more frequently than specific nouns. Starting with core words gives the AAC user the ability to communicate about many different topics with a relatively small vocabulary set.
Step 4: Model, Model, Model
Modeling is the single most effective strategy for teaching AAC. This means that communication partners use the AAC system themselves during conversations. When you want the child or adult to say "more," you point to or tap "more" on their AAC system while saying the word aloud. Research shows that consistent modeling is the strongest predictor of AAC success.
Step 5: Create Communication Opportunities
Rather than only offering AAC during structured therapy sessions, integrate it into everyday activities. Mealtimes, play, daily routines, shopping trips, and social interactions all provide natural opportunities to practice communication. The more opportunities someone has to use their AAC, the faster they will become proficient.
Step 6: Be Patient and Persistent
Learning to use AAC takes time, just as learning any language does. A child learning to speak typically hears language for 12 to 18 months before saying their first word. AAC learners also need extensive exposure before they begin using their system independently. Celebrate every communication attempt, even if it is not perfect.
Tips for Communication Partners
Communication partners, the people who interact with AAC users, play a crucial role in the success of AAC. Whether you are a parent, teacher, therapist, sibling, friend, or caregiver, here are evidence-based strategies for supporting AAC communication:
⏱ Allow Extra Time
AAC communication is slower than speech. Give the person time to compose their message without jumping in to finish their sentences. Wait at least 10 to 15 seconds before prompting or offering help.
💬 Model AAC Use
Use the AAC system yourself when you talk. Point to symbols, type words, or select phrases on the device as you speak. This is the most powerful way to teach AAC, far more effective than instruction or drills.
🔍 Follow Their Lead
Respond to what the person communicates, even if it is a single word or symbol. Build on their message rather than redirecting to what you think they should say. Honor their communication intent.
🤝 Presume Competence
Assume the person has something meaningful to say and the capacity to learn. Speak to them at their age level. Provide access to a robust vocabulary rather than limiting choices to simple requests.
🎯 Create Opportunities
Set up situations where communication is naturally needed. Offer choices, ask open-ended questions, and create moments of anticipation or surprise that motivate communication.
📚 Keep Learning
Learn the AAC system yourself so you can troubleshoot, model effectively, and keep up with the user as their skills grow. Attend training sessions and connect with other AAC families for support.
Common Myths About AAC
Misconceptions about AAC can delay access to communication tools and discourage families from exploring their options. Here are some of the most common myths, corrected with evidence-based facts:
Myth: AAC will prevent speech development
Fact: Decades of research have consistently shown that AAC does not hinder speech development. In fact, many studies show that AAC use can actually promote speech. When individuals have a reliable way to communicate, the pressure and frustration around speech is reduced, and many people begin using more spoken words alongside their AAC system. A comprehensive review published in the journal Augmentative and Alternative Communication found no evidence that AAC inhibits speech and significant evidence that it supports it.
Myth: A person must demonstrate certain skills before they can use AAC
Fact: There are no prerequisite skills for AAC. The outdated idea that someone must demonstrate cognitive abilities, pass certain tests, or reach developmental milestones before receiving AAC has been thoroughly debunked. Current best practices advocate for providing AAC access as early as possible, with the understanding that the system can be adapted and expanded as skills develop.
Myth: AAC is only for people who cannot speak at all
Fact: AAC benefits anyone whose speech is insufficient to meet their daily communication needs. Many AAC users have some speech that may be unclear, unreliable, or limited in certain situations. AAC supplements their existing speech, providing an alternative when words are difficult to produce. Even people with intermittent speech difficulties, such as those who lose words when tired, stressed, or overstimulated, can benefit from having AAC available.
Myth: The person is too young (or too old) for AAC
Fact: There is no age that is too young or too old for AAC. Children as young as 12 months can begin using simple AAC systems, and adults at any age can learn new communication methods. For progressive conditions like ALS, starting AAC early, before speech is significantly affected, provides the best outcomes and allows the person to become proficient with the system while they still have maximum physical ability.
Myth: AAC is too complicated for my loved one to learn
Fact: Modern AAC systems come in many levels of complexity, and a good system is configured to match the individual's current abilities. Starting simple and gradually expanding is a proven approach. Today's AAC apps, like SpeakAid, use AI to reduce the complexity of communication by predicting phrases and adapting to the user's patterns over time.
AAC and Modern Technology
The world of AAC has been transformed by modern technology. Just a decade ago, dedicated AAC devices could cost $8,000 to $15,000 and were often bulky, fragile, and socially stigmatizing. Today, powerful AAC software runs on the smartphones and tablets that people already carry, dramatically reducing cost and increasing accessibility.
How AI Is Changing AAC
Artificial intelligence is the newest frontier in AAC technology. AI-powered features in apps like SpeakAid include:
- Phrase prediction: AI learns from your communication patterns and suggests complete phrases, reducing the number of taps needed to express a thought
- Contextual awareness: The system considers time of day, location, and recent communication to suggest relevant vocabulary
- Natural language generation: AI helps construct grammatically correct sentences from minimal input, making communication sound more natural
- Adaptive learning: The system becomes more accurate over time as it learns the individual's communication style and preferences
The Advantage of AAC Apps
AAC apps on smartphones and tablets offer several advantages over traditional dedicated devices:
- Cost: Apps are dramatically less expensive than dedicated devices
- Portability: A phone is always in your pocket, making AAC always available
- Social acceptance: Using a phone app is socially unremarkable, reducing stigma
- Updates: Apps receive regular updates with new features and improvements
- Familiar technology: Many people already know how to use a smartphone or tablet
- Backup and sync: Vocabulary and settings can be backed up to the cloud
The combination of AI, affordable hardware, and thoughtful app design means that high-quality AAC is more accessible than ever before. What once required thousands of dollars and specialized equipment is now available to anyone with a smartphone.