An establishing operation (EO) is any event, condition, or change in the environment that temporarily makes a particular consequence more effective as a reinforcer and increases behaviors associated with getting that consequence. If you’ve gone several hours without eating, that food deprivation is an establishing operation: it makes food more rewarding and increases the likelihood you’ll do things that have gotten you food in the past, like opening the fridge or driving to a restaurant.
The concept was introduced by behavior analyst Jack Michael in 1982 and has become a foundational piece of applied behavior analysis (ABA). Understanding it helps explain why the same person responds differently to the same situation at different times.
The Two Defining Effects
An establishing operation does two things simultaneously. First, it changes how valuable a particular reinforcer is at that moment. This is called the value-altering effect. Second, it changes how frequently you engage in behaviors connected to that reinforcer. This is the behavior-altering effect. These two effects always work together.
Consider a long run on a hot day. The exercise and heat act as an EO for water. The value-altering effect is that water becomes a much more effective reinforcer than it was before the run. The behavior-altering effect, called the evocative effect, is that you’re now more likely to do things that have previously led to getting water: walking to a water fountain, asking someone for a bottle, or reaching into your bag for your own. Before the run, water was available in all those same places, but you weren’t motivated to pursue it. The EO changed both how much you wanted it and how hard you’d work to get it.
Where EOs Fit: The Motivating Operation Framework
Michael originally used “establishing operation” as a broad umbrella term for any antecedent event that altered the value of consequences. In 2003, researchers proposed cleaner terminology. The umbrella term became “motivating operation” (MO), with two subtypes beneath it:
- Establishing operations (EOs) increase the effectiveness of a reinforcer and evoke related behavior. Food deprivation is an EO for food.
- Abolishing operations (AOs) decrease the effectiveness of a reinforcer and reduce (abate) related behavior. Eating a large meal is an AO for food.
So every establishing operation is a motivating operation, but not every motivating operation is an establishing operation. If you see “MO” in a textbook, it’s the general category. “EO” specifically refers to the kind that ramps things up.
Unconditioned vs. Conditioned EOs
Some establishing operations don’t require any learning history. These are unconditioned EOs, and they’re rooted in biology. Food deprivation, water deprivation, sleep deprivation, temperature extremes, and painful stimulation all function as EOs without anyone having to teach you that they matter. Going without sleep makes a comfortable bed more reinforcing and increases behavior that has led to sleep in the past. A sudden drop in temperature makes warmth more reinforcing and evokes behaviors like putting on a jacket or turning up the thermostat.
Conditioned EOs, by contrast, gain their motivating properties through learning. They’re stimuli or situations that have been paired with unconditioned EOs or with access to (or removal from) reinforcers over time. A warning light on your car’s dashboard, for example, doesn’t naturally increase the value of anything. But because it’s been associated with the possibility of a breakdown (an aversive event), it establishes removal of that threat as a reinforcer and evokes behavior like pulling over or calling a mechanic.
How EOs Differ From Discriminative Stimuli
This is one of the most common points of confusion in behavior analysis. A discriminative stimulus (SD) signals that a reinforcer is available if you perform a certain behavior. An establishing operation changes whether you care about that reinforcer in the first place.
Think of a vending machine. The sight of the machine is an SD: it tells you that if you insert money, you’ll get a snack. But whether you actually walk over and buy something depends on your current state of food deprivation or satiation, which is the EO. Michael’s original definition of the SD even built this in explicitly, noting that it increases a behavior’s frequency “given the momentary effectiveness of some particular type of reinforcement.” That momentary effectiveness is set by the EO.
In practice, the two interact constantly. An SD strongly influences which specific behavior you perform when an EO is in effect, and the EO determines whether a given SD actually triggers any responding at all. A person who just finished a huge meal might walk right past that vending machine without a second glance. The SD is present, but the EO is not.
Practical Applications in Therapy
Clinicians working in applied behavior analysis routinely manipulate EOs to teach new skills and reduce problem behavior. One common approach involves controlling access to preferred items to create the motivation needed for communication training. If a child is learning to request a toy using a picture card, the therapist first restricts access to that toy (creating an EO), then teaches the child that handing over the card produces the toy. When the child already has free access to the toy, the AO is in effect and there’s no motivation to use the card.
This EO manipulation also serves as a way to test whether a person has truly learned a functional communication skill. If a child requests an item when they already have it, the request probably isn’t a genuine, motivated communication. But if they request it only when it’s been withheld and stop requesting when they have free access, that pattern confirms the request is controlled by the EO, meaning it’s a true, functional mand (a request driven by actual motivation). Research has shown this kind of testing helps clinicians distinguish real communicative behavior from rote responding.
The same principle works in reverse for reducing problem behavior. If a child’s tantrums are maintained by attention, providing frequent, high-quality attention throughout the day acts as an AO: it reduces the value of attention as a reinforcer and decreases the tantrums that previously produced it. By identifying which EOs are driving problem behavior through functional assessment, clinicians can address the underlying motivation rather than just reacting to the behavior itself.
Why the Concept Matters
Before the EO framework, behavior analysis focused heavily on the relationship between a behavior and its consequences (reinforcement and punishment) and on the signals that preceded behavior (discriminative stimuli). What was missing was a systematic way to talk about motivation. The establishing operation filled that gap by giving practitioners a precise term for the conditions that make consequences matter more or less at any given moment.
This has real implications for anyone working with behavior, whether in a clinical, educational, or everyday setting. If you’re trying to teach someone a new skill and they’re not responding to your reinforcer, the issue might not be the reinforcer itself or the teaching method. The EO might simply not be in place. Recognizing that distinction can save enormous time and frustration, because the solution shifts from changing the consequence to changing the antecedent conditions that give that consequence its power.