Functional communication training (FCT) is an ABA intervention that teaches children with autism and other developmental disabilities to replace challenging behaviors with socially appropriate communication. Instead of acting out to get a need met, the child learns a better way to ask. FCT can use speech, sign language, pictures, or communication devices depending on what works best for the individual child.
If your child’s therapist just mentioned functional communication training, you’re probably wondering what it actually means and whether it will help. You’re not alone. FCT is one of the most widely used interventions in ABA therapy, and for good reason. It gets at something most behavioral challenges have in common: the child is trying to communicate something, just not in a way that works for everyone around them.
This guide breaks down what FCT is, how it’s implemented, and what you can realistically expect from the process.
What Is Functional Communication Training?
Functional communication training is a behavioral intervention designed to replace challenging or problem behaviors with functional communication. The term “functional” is key here. It means the communication serves a real purpose for the child. They’re not just learning words or gestures for the sake of it. They’re learning to use a better tool to get what they need.
FCT was first formally described in the research literature in 1985 by Carr and Durand and has since become a core strategy within applied behavior analysis. It’s often categorized as a positive behavior support intervention, meaning it focuses on building new skills rather than simply eliminating unwanted behaviors.
ABA practitioners use FCT with children who are non-verbal, minimally verbal, or who have limited communication skills that make it hard for them to express their wants and needs in socially acceptable ways.
Why Challenging Behaviors Happen
To understand FCT, it helps to understand why challenging behaviors occur in the first place. In ABA, a functional behavior assessment (FBA) is used to determine the purpose a behavior serves for a child. This is called the function of the behavior.
In ABA, challenging behaviors are commonly categorized into four main functions: attention, access to tangible items or activities, escape/avoidance, and automatic (sensory) reinforcement. When a child can’t communicate these needs effectively, frustration builds fast. And when frustration builds, behavior often escalates.
Here’s what’s important to understand: the behavior is typically being reinforced in some way, meaning it results in attention, access, escape, or sensory input. The child isn’t acting out to be difficult. The behavior is getting them something. The goal of FCT isn’t to punish that behavior. It’s to give the child a better strategy that works just as well, or better.
How FCT Is Implemented in ABA
FCT follows a structured process, but it’s not a rigid script. A qualified ABA practitioner, typically a Board Certified Behavior Analyst (BCBA), tailors each step to the individual child. Here’s how it generally works.
The BCBA starts by assessing the challenging behavior. This means identifying what the behavior looks like, when it happens, and most importantly, what function it serves. That assessment directly shapes everything that follows.
Next, the practitioner selects an appropriate communication replacement. This is the new skill the child will learn to use instead of the problematic behavior. It has to be something the child can actually do, and it has to be efficient enough to produce the same result as the old behavior quickly.
From there, the BCBA systematically teaches the new communication skill. Prompting plays a big role in this stage, guiding the child toward the target response and then gradually fading that support as the child gains independence.
Once the child starts using the new communication method, consistent reinforcement is critical. Every time the child uses the desired communication, they get the outcome they’re looking for. Meanwhile, the old problem behavior is no longer reinforced when it is safe and appropriate to do so, and when a functional alternative has been established. That last part matters just as much as teaching the new skill.
Communication Modalities Used in FCT
FCT doesn’t require a child to speak. That’s one of the reasons it’s so effective across such a wide range of learners. The communication form used depends entirely on what’s functional and achievable for the individual child.
Some children learn to use spoken words or phrases. Others use sign language, which can be a powerful option for children who have the motor control for it but not yet the verbal output. Picture exchange communication systems (PECS) are commonly used with children who are non-verbal or who respond well to visual cues. Augmentative and alternative communication (AAC) devices, including tablets with communication apps, are increasingly part of the toolkit.
Visual supports, more broadly, can also play a supportive role in FCT by helping children understand routines, expectations, and how to access communication tools throughout their day. The right modality is the one the child can use consistently, and that gets them what they need quickly enough to compete with the old behavior.
What to Expect from the FCT Process
FCT is not a quick fix. That’s worth saying plainly. Teaching a new communication skill and getting a child to use it reliably, in the moment when they’d normally act out, takes time. Depending on the child and the complexity of the behavior, it can take weeks or even months to see consistent results.
Here’s a real-world example. A non-verbal child with ASD would bang her head on the table whenever she wanted more juice. The behavior worked. Her mother would refill the cup. But it wasn’t safe, and it wasn’t sustainable.
The BCBA introduced a replacement behavior: tapping the cup on the table. Through practice with the mother, the child learned that tapping the cup led to a refill. Gradually, the mother only responded to the cup tap and ignored the head banging. Over time, the head banging decreased, and the cup tap became the child’s go-to communication.
That’s FCT working as intended. The child didn’t lose her ability to get juice. She gained a safer, more socially acceptable way to ask for it.
A few factors tend to shape how quickly FCT produces results: how consistently the new behavior is reinforced across settings, whether everyone in the child’s life is on the same page, and how well the replacement behavior matches the function of the original behavior. The more aligned those factors are, the better the outcomes tend to be.
Frequently Asked Questions
What behaviors can FCT address?
FCT can be used with a wide range of challenging behaviors, including aggression, self-injury, property destruction, tantrums, non-compliance, and escape behaviors. What these behaviors have in common is that they serve a communicative function for the child. FCT is most appropriate when a behavior has a clear communicative function identified through assessment.
Who delivers FCT?
FCT is typically designed and supervised by a Board Certified Behavior Analyst (BCBA). In many cases, a Registered Behavior Technician (RBT) delivers direct therapy sessions under the supervision of a BCBA. Parents and caregivers are also trained to implement FCT strategies at home, which is important for consistency across environments.
Does the child need to be verbal for FCT to work?
No. FCT is designed to work for non-verbal and minimally verbal children as well as those who can speak. The communication form is chosen based on what the child can realistically use. Sign language, picture systems, and AAC devices are all common alternatives to spoken language in FCT programs.
How is FCT different from just punishing the problem behavior?
FCT focuses on building a new skill rather than punishing an old one. Extinction, the process of no longer reinforcing the problem behavior, is often part of the plan. But it works alongside teaching because the child needs a functional replacement before the old behavior is phased out. FCT without teaching an alternative isn’t FCT.
How long does FCT take to work?
There’s no universal timeline. Some children show progress within a few weeks. Others need months of consistent practice before the new communication becomes reliable. Progress depends on the child’s current skill level, the consistency with which the program is implemented across settings, and how closely the replacement behavior matches the function of the original behavior.
Key Takeaways
- FCT replaces behaviors with communication that serves the same function, giving the child a better tool rather than simply trying to stop a problem behavior.
- Assessment comes first. FCT starts with understanding why the behavior is happening, not just what it looks like.
- Communication doesn’t have to be verbal. Sign language, picture systems, and AAC devices are all valid options depending on the child’s needs and abilities.
- Consistency is everything. Reinforcing the new skill and stopping reinforcement of the old behavior both have to happen reliably across all settings.
- Everyone has to be on the same page. FCT works best when parents, teachers, and therapists consistently implement the approach.
Ready to learn more about ABA therapy and the professionals who deliver it? Whether you’re a parent exploring options or someone considering a career in ABA, we can help you find the right path forward.
