Master ABA

Errorless Learning: Complete Guide

The field of Applied Behavior Analysis (ABA) offers many different teaching methodologies. Each child learns in a unique way and teaching plans must cater to each child’s specific learning style. Errorless learning (EL), also called errorless teaching, provides structure for teaching, but what do you really know about it?

With errorless learning, instructors use prompting to ensure the learner responds correctly every time (hence “errorless”). Prompts can involve varying degrees of intrusiveness, and must be correctly faded to prevent dependence on prompts. While the concept is easy to understand, putting it into practice takes some skill.

Obtaining Assent

Assent is a learner’s agreement to participate in an intervention. It is important to obtain assent from learners during ABA interventions, even those with limited communicative ability. Assent can be obtained in a variety of ways, depending on the learner’s individual needs and preferences.

One way to obtain assent is to ask the learner directly if they want to participate in the intervention. The practitioner should use simple language and be clear about what the intervention will involve. If the learner is nonverbal, the practitioner can use gestures or other methods of communication to ask for and observe assent.

Another way to obtain assent is to offer the learner a choice. For example, the practitioner could say, “Would you like to do this activity with me or with your parent?” This gives the learner a sense of control and allows them to express their preferences.

It is also important to respect the learner’s decision, even if they choose not to participate in the intervention. The practitioner should evaluate the intervention or activity to determine why the learner might have withdrawn assent. By changing the intervention, activity or even the timing of the presentation, the practitioner may be able to obtain assent at another opportunity.

There are a number of benefits to obtaining assent from learners during ABA interventions. First, it shows respect for the learner’s autonomy and right to make their own decisions. Second, it can help to build trust and rapport between the learner and the practitioner. Third, it can increase the learner’s motivation to participate in the intervention.

Assent can be obtained from learners with all levels of communicative ability. For example, a learner who can speak can simply say “yes” or “no” to indicate their assent or assent withdrawal. A learner who is nonverbal may use gestures, facial expressions, or body positioning to indicate their assent. The learner can also use other methods of communication, such as AAC assent from learners who are nonverbal.

As with any treatment, the strategies discussed here should only be used with the assent of the learner. Read our post Understanding Assent and Assent Withdrawal in ABA for more information on how and why to obtain assent.


How to use Errorless Learning 4 Steps to Implementing Errorless Learning Fading Prompts Least to Most (LTM) Most to Least (MTL) Time Delay Prompt Fading 3 Things You Should Know about Errorless Learning Important Considerations Examples of Errorless Learning

Related Posts

How to use Errorless Learning

This image shows 3 types of prompts, physical, verbal and visual in order from most intrusive at the top and least intrusive at the bottom.  Each of these can be further broken down. For example, a verbal prompt may be a partial prompt, such as an open-ended question. “What would you do next?” is an example of an indirect partial verbal prompt. This would be considered less intrusive than a direct verbal prompt like, “Pick up the books.“

When using errorless learning, begin with prompts that are more intrusive, then move down the hierarchy until your learner can complete the task correctly. If your learner requires a direct verbal prompt to respond correctly, start teaching at that prompt level and begin to fade the prompt as the learner becomes successful. Use the least prompting possible while ensuring your learner can perform the task correctly.


Physical prompts involve some form of contact between you and the student.  Many schools regulate the use of physical prompts, so know the rules in your school before using them.  Physical prompts include full, partial and light touch and shadow.  An example includes placing your hand over the student’s hand to perform a task such as writing his name.


Verbal prompts can be direct or indirect. An indirect prompt would be considered one of the least intrusive types of prompts. This would be an open-ended question that allows your student to remember what they need to do mostly on their own. Ask questions like, “What do you need to do next?” or “How would you start?“

If this isn’t effective you can use a direct verbal prompt such as, “Now cross the laces and slide one end under the other.”


Visual prompts involve some type of cue to signal to the student what he should do or what the correct answer is.  These prompts include model, stimulus, positional and gestural prompts.  Visual schedules are a type of prompt that allows your student to see each step of task.

As your learner gets more comfortable with the new skill gradually fade the prompts (prompt fading is discussed below).

For an in-depth discussion on prompting read our post Prompt Hierarchy: A New Perspective.

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4 Steps to Implementing Errorless Learning

Errorless learning requires the instructor to follow 4 steps for implementation. In order to minimize the likelihood of prompt dependence and maximize learning, you must carefully implement each step.

Step 1: Identify the skill to be taught and how you will know the learner has mastered the skill

To begin implementing errorless learning, first identify the skill you want to teach and the mastery criteria for that skill. For example, you decide to teach the child to tact “cat.” You then decide that the learner meets mastery criteria when he responds correctly during 9 out of 10 trials during 3 consecutive teaching sessions without prompts.  

Some examples of skills that lend themselves to using this strategy include

  • Academic tasks such as letter recognition, sight words, or shapes  
  • Communication skills, including  receptive skills such as responding to verbal prompts and expressive skills such as asking for something they want 
  • Life skills such as cooking or hand washing  

Step 2: Identify the level of prompt needed to ensure a correct response

The second step is to identify the level of prompt needed to ensure that the learner responds correctly.  This will typically be done based on experience with your learner and what has been successful in the past.  Here’s a quick review of the different types of prompts you may choose:  

  • —Physical-Learner cued by moving part of learner’s body—
  • Gestural-Nonverbal cue such as pointing—
  • Verbal-Vocal cue that could be a phrase or syllable—
  • Visual-Picture or text cue—
  • Modeling-Correct response is demonstrated—
  • Positional-Item placed to increase likelihood of correct response

When selecting the level or type of prompt you will use, develop a plan for fading this prompt that can be used later in this process.  This plan reduces the risk of the child becoming prompt dependent.

Step 3: Begin the teaching trial

In the third step, the instructor begins the teaching trial. Start by presenting the discriminative stimulus (SD). Immediately provide the level of prompt identified in Step 2.  Attempt to block and physically prompt your learner if you observe the learner is about to make an error.  

If your learner responds correctly, provide immediate positive reinforcement.  Effective implementation requires that you accurately identify what motivates your learner.  If your learner responds incorrectly, increase the level of prompt that you use during the next trial and complete an error correction procedure. For example, if you believed that a gestural prompt would be sufficient, but the learner still made an error with this type of prompt, it would be appropriate to use a physical prompt during the next trial.

Step 4: Repeat trials, systematically fade prompts to ensure continued correct responses until the learner is able to respond independently at the level identified during Step 1.

The final step in the process is to repeat the trials while systematically fading the prompts to ensure that the learner continues to respond correctly.  You will continue this process until the learner has reached the level identified during step 1.  

Here’s an example of prompt fading.  If you have decided to use physical prompts and you begin the first trial with hand over hand prompting, you would begin to fade this prompt by moving your hand to the learner’s wrist, then gradually moving the prompt up the arm.  If at any point, the learner responds incorrectly, return to the last level of prompting that produced a correct response then continue to fade the prompt gradually.  Each of the different types of prompt requires a different method of fading the prompt. 

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Fading Prompts

When your learner masters the skill with the chosen prompt, begin fading the prompt. Be sure to fade the prompt gradually, ensuring that the learner masters the skill at each level before continuing to fade.

Fading prompts might mean changing the type of prompt you are using.  For example, if you begin with a full physical prompt as discussed in the hand washing example above, you might face the prompt to be a gentle touch on the hands at different steps.  Over time you might fade this further to a visual prompt or maybe a verbal one.  But prompt fading can also just reduce the selected prompt until no prompt is needed.  For example, these mazes fade the dots that teach a learner how to follow a maze.

These mazes use three levels to fade the prompt. In level 1 you can clearly see the path from the dog to the bone. Level 2 increases the distance between dots, requiring the student to understand for themselves how to navigate the maze a little to get from one dot to the next. Level 3 removes all of the dot prompts so that your learner must complete the maze on their own.

There are 3 options to choose from when fading prompts:

  • Least to most
  • Most to least
  • Time delay
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Least to Most (LTM)

When prompting using the least to most strategy, instructors begin with the least intrusive prompt and increase the intrusiveness of the prompt until they receive a correct response. With every trial, the instructor repeats this process of moving from least intrusive prompt to more intrusive until the learner provides a correct response.

This method of errorless learning provides opportunity for the learner to provide a correct response with the least amount of prompting at each trial, and may allow him to demonstrate independence earlier than with the other types of prompt fading. This option may be ideal for learners who have already shown success with this prompting method (Libby, M., Weiss, J., Bancroft, S., Ahearn, W., 2008).

Example of Least to Most Prompt Fading
Trial 1Trial 2Trial 3Trial 4
Teacher: Teacher holds up handTeacher: Teacher holds up handTeacher: Teacher holds up handTeacher: Teacher holds up hand
Learner: No responseLearner: No responseLearner: No responseLearner: Learner gives teacher a high 5
Teacher: “High 5” Teacher: “High 5” Teacher: “High 5”
Learner: No responseLearner: No responseLearner: Learner gives teacher a high 5
Teacher: “High 5” (teacher moves hand closer to learner)Teacher: “High 5” (teacher moves hand closer to learner)
Learner: No responseLearner: Learner gives teacher a high 5
Teacher: “High 5” (teacher moves learner’s hand to her hand)
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Most to Least (MTL)

With most to least prompt fading, the instructor identifies the prompt required and begins with the most intrusive prompt. In the example above, the first trial would start with the physical prompt as the learner is unable to complete the task without a physical prompt. Initial trials to establish a baseline may be needed if the instructor is unsure of the learner’s skill level.

Research shows that, in general, the most to least prompt fading method leads to fewer errors by the learner in each session, and often leads to faster skill acquisition than least to most. MTL may be preferable if errors reduce a child’s learning or increase problem behavior. Combining MTL with a time delay (discussed below) may produce even faster acquisition (Libby, M., Weiss, J., Bancroft, S., Ahearn, W., 2008).

Example of Most to Least Prompt Fading

Let’s look at how the example for LTM would be different if MTL were being used:

Trial 1Trial 2Trial 3Trial 4
Teacher: “High 5” (teacher moves learner’s hand to her hand)Teacher: “High 5” (teacher moves hand closer to learner)Teacher: “High 5” Teacher: Teacher holds up hand
Learner: Learner gives teacher a high 5Learner: Learner gives teacher a high 5Learner: Learner gives teacher a high 5

Data Collection for Least to Most and Most to Least

As with any ABA strategy, collecting data is critical to the success of these interventions to reduce the likelihood of prompt dependence. Download the data sheet below as an example:

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Time Delay Prompt Fading

Additionally, delaying the amount of time between the cue for the learner to complete the behavior and delivering the prompt is another type of prompt fading. By delaying prompts, you give the learner an opportunity to give a correct response on their own. This delay is gradually increased as the learner becomes more independent. Correct responses completed without prompting are immediately reinforced.

Constant and Progressive Time Delay

Both constant time delay (CTD) and progressive time (PTD) delay are similar, except for one key point. With CTD the delay is immediate and doesn’t change. With PTD the delay increases gradually as the learner becomes more proficient. While both methods can be effective, evidence exists that CTD may result in more errors (Walker, G., 2008). The discussion here will focus on PTD, however CTD can be implemented in the same fashion by using a constant delay interval.

Data Tracking

An important component of time delay prompt fading is data tracking to measure the learner’s progress (Neitzel, J., & Wolery, M. ,2009). Baseline data is collected at 0-second intervals (prompts are given without delay) before introducing delays in prompts. Download this data tracking sheet to get started:

Example of Time Delay Prompt Fading

Trial 1
(0 second delay)
Trial 2
(2 second delay)
Trial 3
(2 second delay)
Trial 4
(2 second delay)
Trial 5
(3 second delay)
Teacher holds a card with the letter A and asks, “What letter is this?” She then immediate says, “This is the letter A.”Teacher holds a card with the letter A and asks, “What letter is this?” She then waits to 2 seconds before saying, “This is the letter A.”Teacher holds a card with the letter A and asks, “What letter is this?” She then waits to 2 secondsTeacher holds a card with the letter A and asks, “What letter is this?” She then waits to 2 secondsTeacher holds a card with the letter A and asks, “What letter is this?” She then waits to 2 seconds
Student repeats, “A.”Student repeats, “A.”Student responds, “A.”Student responds, “A.”Student responds, “A.”
Teacher praises the child, “Nice job” and gives a reinforcer.Teacher praises the child, “Nice job” and gives a reinforcer.Teacher praises the child, “Nice job” and gives a reinforcer.

Reinforcement with Time Delay Fading

As with any ABA strategy, having a plan for effective reinforcement is key to the success of this intervention. Prompted responses should be reinforced at a lower rate than unprompted responses. Decide ahead of time what you will use for each to ensure each is reinforced appropriately.

Create Your Plan

Because of the nature of time delay prompt fading, planning is instrumental. When creating your plan be sure to include:

  1. Target behavior definition
  2. Delay interval
  3. Reinforcer for unprompted response
  4. Reinforcer for prompted response
  5. Mastery criteria
  6. Action to take when mastery criteria is met

Let’s look at an example:

Target behavior: Learner will correctly identify the word “cat” on a flashcard 9 out of 10 trials across 3 sessions.

Reinforcer for unprompted response: Mini M&M

Reinforcer for prompted response: Verbal praise, “Good job!”

Delay IntervalMastery CriteriaAction to Take
0 secondsResponds correctly to SD 9 out of 10 trials across 3 sessionsIf yes, increase interval to 2 seconds; if no, remain at 0 seconds
2 secondsResponds correctly to SD 9 out of 10 trials across 3 sessionsIf yes, increase interval to 4 seconds; if no, remain at 2 seconds or return to 0 seconds
4 secondsResponds correctly to SD 9 out of 10 trials across 3 sessionsIf yes, increase interval to 6 seconds; if no, remain at 4 seconds or return to 2 seconds
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3 Things You Should Know about Errorless Learning

During errorless learning, or errorless teaching, professionals attempt to eliminate mistakes made by the learner. The instructor uses prompts to ensure correct responding and then systematically fades the prompts. Here are the 4 things you need to know before you get started:

  1. Errorless learning is an antecedent intervention
  2. There are many advantages and disadvantages
  3. Errorless learning isn’t appropriate for every learner

1. Errorless Learning is an Antecedent Intervention

Errorless learning is an antecedent intervention from Applied Behavior Analysis (to learn more about antecedent interventions read our post Antecedent Interventions: Complete Guide) . This method of teaching skills minimizes opportunities for errors, increasing the frequency at which the child encounters reinforcement. Minimizing errors also reduces the likelihood that the child engages in challenging behavior.

Instructors use prompts to support the learner in responding correctly. The instructor then systematically fades the prompts to promote independent responding.

When an instructor first introduces a new skill acquisition target, she utilizes most to least prompting. If she decides to errorlessly teach the child to clap his hands when she says “clap your hands,” she begins by providing the SD and immediately uses a full physical prompt. She then systematically fades the prompt through the prompt hierarchy until the child responds independently.

prompt hierarchy

The above graphic depicts common prompting strategies in relative order from most intrusive to least intrusive (from the base to the point of the triangle). Keep in mind that there are many other prompting strategies (i.e. positional prompts, within stimulus prompts, or model prompts) that would fall at various levels along this continuum depending on the particular needs of your learner. Additionally, carefully consider the use of verbal prompts as these prompts are often exceptionally hard to ultimately eliminate. For more on the prompt hierarchy read our post Prompt Hierarchy: A New Perspective.

Download our infographic for reference:

2. There are Many Advantages and Disadvantages

Errorless learning offers some important advantages you should consider.

Minimizes mistakes and decreases the likelihood errors will be repeated in the futureLearners can become dependent on the prompt to complete the task
Reduces frustration and problem behaviors that result from frustrationFading prompts is a skill that takes practice, even for professionals.
Provides more opportunities for reinforcement which creates a positive learning environmentIf prompts are not faded correctly your learner might fail to learn the desired behavior.

Errorless learning minimizes mistakes made by the learner and decreases the likelihood that errors will be repeated during future trials.  Many children with autism quickly develop inappropriate behavior chains when instructors wait for errors before providing prompts.

For example, one child I worked with learned to complete a foam alphabet puzzle. She put the pieces in the puzzle sequentially, but before putting in each piece, she brought the piece to her mouth and licked it. If she used errorless learning to teach puzzle completion, she would have been less likely to develop this inappropriate behavior chain. To learn more about behavior chains read our post Behavior Chains: Using Task Analysis for Chaining.

This strategy reduces the learner’s frustration and any problem behavior that may be associated with it.  Errorless learning provides more opportunities for reinforcement than traditional teaching methods and increases the time available for instruction as problem behaviors are reduced or eliminated.

While errorless learning offers many advantages, you must consider this distinct disadvantage before you implement the intervention. The primary disadvantage of EL is that learners may become dependent on the prompts used to assist them in responding correctly.  This teaching strategy requires the instructor to be able to systematically fade the prompts so that the learner eventually responds correctly without the prompts. In the beginning, it can be difficult for teachers to do this effectively.

3. Errorless Learning Isn’t Appropriate for Every Learner

Errorless learning can be used in a variety of situations.  Although it can be tempting to use EL with all of your learners, you must carefully consider the needs of each individual. Here are some of the best uses of errorless learning:

  • It may be appropriate if you are working with a learner who is struggling to learn a new skill through traditional teaching strategies.  
  • You may choose errorless learning when new tasks or mistakes cause the learner to engage in problem behaviors.  
  • It can also be a valuable tool when working with learners who develop routines quickly and may repeatedly respond incorrectly because it is part of a routine. 

Avoid using errorless learning for learners who:

  • Acquire skills quickly with traditional teaching methods
  • Easily become prompt dependent
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 Important Considerations

Here are a couple of important things to keep in mind.  Before you begin using the errorless learning procedures, it’s essential to understand what motivates your learner.  Every correct response must be followed by something that motivates your learner.  This is the essence of positive reinforcement.  

A cookie may be motivating to you but not necessarily your learner.  The same holds true for a high five, praise, bubbles and anything else we may typically think children like.  In order for EL to be effective, you must know what motivates the individual you are working with.  

The second thing to keep in mind is to always end a session on a successful trial.  You never want to end a teaching session after the learner makes a mistake.  If the learner makes a mistake on the trial you had planned to end with, conduct another trial, increasing the level of prompt to ensure a correct response, and provide reinforcement before ending the session. 

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Examples of Errorless Learning

Mrs. Smith-Step 1

Mrs. Smith works with a 5-year-old student with autism.  She decides to use errorless learning to teach her student to correctly identify shapes.  Mrs. Smith completes step 1 of the process by deciding the first shape she will teach her student to identify is a circle.  She will teach her student to choose a circle when given 2 additional shapes, which will be a square and a triangle. She identifies mastery criteria as 80% correct responding for 3 consecutive sessions.

Mrs. Smith-Step 2

Mrs. Smith progressed to Step 2 of the process.  Through her past experiences with this particular student, Mrs. Smith believes that a visual prompt would help her student respond most successfully.  She prepares her flashcards so that the circle flashcard is a bold black and the square and triangle flashcards are a faded gray. 

Mrs. Smith-Step 3

Moving on to Step 3, Mrs. Smith begins the first trial by placing the 3 flashcards on the table in front of the student.  She asks her to “Find the circle.”  When the student raises her hand and begins to move toward the square flashcard, Mrs. Smith gently takes the student’s hand and guides it to the circle flashcard. Mrs. Smith remarks, “That’s the circle!” and gives her student a piece of her favorite cereal.

Mrs. Smith-Step 4

Mrs. Smith repeats the trial, providing reinforcement during each trial when her student selects the circle flashcard.  After 3 trials of successfully selecting the correct flashcard, Mrs. Smith pulls out the next set of triangle/square flashcards that are just a bit darker than the first set used during the first trials.  Mrs. Smith continues to offer reinforcement for correct responses.  She gradually fades the prompt by introducing subsequently darker triangle/square flashcards through many trials until those flashcards are as dark as the circle flashcards and the student is able to identify the circle without the prompt.


Libby, M., Weiss, J., Bancroft, S., Ahearn, W. (2008). A Comparison of Most-to-Least and Least-to-Most Prompting on the Acquisition of Solitary Play SkillsBehav Anal Pract. Spring; 1(1): 37–43. Published online Spring 2008. doi: 10.1007/BF03391719

Neitzel, J., & Wolery, M. (2009). Steps for implementation: Time delay. Chapel Hill, NC: The National Professional Development Center on Autism Spectrum Disorders, Frank Porter Graham Child Development Institute, The University of North Carolina.

Touchette, P., & Howard, J. (1984). Errorless Learning: Reinforcement Contingencies and Stimulus Control Transfer
in Delayed Prompting
. Journal of Applied Behavior Analysis, 17(2), 175–188.

Walker, G. (2008). Constant and progressive time delay procedures for teaching children with autism: A literature review. Journal of Autism and Developmental Disorders, 38, 261-275.


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