Assent in Behavior Analysis: Ethical Client Involvement and the Clinical Case for Autonomy

Overview & Clinical Significance

Assent refers to an individual's agreement or willingness to participate in an intervention or activity, distinct from legal consent, which is provided by a parent or guardian on behalf of a minor or individual who lacks decision-making capacity. In applied behavior analysis, the growing emphasis on assent reflects a substantive shift in how the field conceptualizes the role of the client in the therapeutic process. Dr. Cody Morris's webinar, presented by Bridget Taylor, makes explicit what the field has been moving toward: that fostering client autonomy and honoring assent is not merely a courtesy—it is a clinical and ethical imperative.

The distinction between consent and assent matters significantly in ABA practice. A parent may provide legally valid consent for an intervention, but that consent does not guarantee the child's willingness to participate. An intervention imposed on a consistently unwilling client, even when technically consented to and clinically indicated, raises questions about behavioral coercion, motivating operations, and the quality of the therapeutic relationship. More practically, interventions conducted over a client's active resistance tend to produce worse outcomes than those implemented with the client's cooperation.

The ethical dimension is equally clear. A field that is committed to producing behavior that is socially significant and that benefits the individual client must grapple with what it means to produce behavior change in someone who has signaled, through behavior, that they do not want the intervention. Assent frameworks provide a structure for taking that signal seriously in ways that improve both the ethics and the effectiveness of clinical practice.

Background & Context

Assent has a longer history in biomedical ethics than in behavior analysis. In pediatric medicine, the concept that children should be meaningfully involved in decisions about their own care—even when legal consent is provided by parents—emerged through bioethics literature in the 1990s and was formalized in guidelines from professional medical associations. The American Academy of Pediatrics and the American Psychological Association have both articulated standards for assent in research and clinical contexts.

Behavior analysis's engagement with assent has been more recent and has been driven in part by broader professional discourse about the ethics of behavior change with populations who cannot provide verbal consent. The neurodiversity movement has been particularly influential, raising challenges to behavior-analytic practice from the perspective of autistic individuals and other disability advocates who have argued that some historically common ABA procedures were implemented without meaningful attention to client welfare and preferences.

Within behavior analysis itself, the concept of assent has been operationalized in several ways. Some researchers and clinicians define assent in terms of observable approach and avoidance behaviors—a client who consistently moves toward materials, initiates interactions, and shows positive affect is providing behavioral assent; one who consistently avoids, cries, or engages in problem behavior is signaling non-assent. Others have developed structured assent protocols that use preference assessments, choice-making opportunities, and explicit communication about intervention options to build assent into program design.

The BACB Ethics Code revisions effective January 2022 incorporated stronger language around client dignity, autonomy, and involvement in treatment decisions. This reflects the field's formal recognition that assent is an ethical requirement, not merely a clinical nicety.

Clinical Implications

The clinical implications of assent in behavior analysis are both structural and procedural. Structurally, programs that incorporate assent must be designed differently from those that simply implement a behavior analyst's clinical plan. Goal selection becomes a collaborative process to the greatest extent possible given the client's communication abilities. Intervention procedures must be assessed not only for efficacy but for acceptability to the client. Treatment data must include measures of client engagement and willingness, not just skill acquisition or behavior reduction.

Procedurally, assent monitoring requires that clinicians attend systematically to behavioral indicators of client cooperation and distress throughout every session. A client who has been participating willingly may signal non-assent partway through a session through avoidance, increased problem behavior, or disengagement. Recognizing and responding to these signals—not merely pushing through to complete a session plan—is a clinical skill that requires explicit training.

For BCBAs, the assent framework also reshapes how intervention is justified. An intervention that produces skill acquisition at the cost of consistent client distress requires additional scrutiny. The analysis is not simply 'does this procedure work?' but 'does this procedure work in a way that is acceptable to this client, and if not, is there an equally effective alternative that produces better cooperation?' This question drives practitioners toward naturalistic, choice-embedded, and motivationally aligned approaches that tend to produce both better outcomes and better assent indicators.

The relationship between assent and motivating operations is clinically important. Operations that establish a given activity as a reinforcer will naturally produce approach; operations that abolish it will produce avoidance. A client who consistently refuses a particular instructional format is providing information about the motivating operations relevant to that context. Rather than treating refusal as problem behavior to be eliminated, assent frameworks treat it as clinically meaningful data that should drive program revision.

Ethical Considerations

The BACB Ethics Code provides direct and specific guidance on assent. Code 2.11 (Obtaining Informed Consent) requires behavior analysts to obtain informed consent from clients or their legal representatives prior to implementing services. While this provision addresses legal consent, its underlying rationale—that people have the right to make meaningful decisions about interventions—applies equally to assent. The 2022 Ethics Code added explicit language on the importance of client dignity and the obligation to consider client preferences in treatment planning.

Code 2.01 (Providing Effective Treatment) requires that BCBAs provide evidence-based services that benefit clients. Interventions conducted over consistent client non-assent are not straightforwardly consistent with this provision. There is growing evidence that interventions implemented in the context of client cooperation and preference alignment produce better outcomes than the same procedures implemented over client resistance. The ethical and the clinical case for assent are therefore convergent.

Code 2.09 (Least Restrictive Procedures) requires that BCBAs use the least restrictive procedures that will achieve intervention goals. The concept of least restrictiveness has historically been applied primarily to consequence-based interventions—physical guidance, planned ignoring, overcorrection—but assent frameworks extend this reasoning to program design broadly. If a client consistently non-assents to a particular instructional format but readily assents to an alternative that produces equivalent outcomes, the less restrictive, more assent-consistent approach is ethically preferred.

Code 1.07 (Exploitative Relationships) and Code 2.02 (Boundaries of Competence) are also relevant. The power differential between a behavior analyst and a non-speaking client is significant, and practitioners must be vigilant about whether their clinical decisions reflect genuine client welfare or the path of least resistance for the provider. Maintaining assent monitoring as a formal part of clinical practice is a structural safeguard against this risk.

Assessment & Decision-Making

Implementing assent monitoring in clinical practice requires developing operationalized definitions of assent and non-assent for each individual client. Because many clients receiving ABA services have limited verbal communication, behavioral indicators must serve as the primary assent signal. Approach behaviors—reaching toward materials, initiating eye contact, moving toward the clinician or activity—are generally treated as assent indicators. Avoidance behaviors—turning away, pushing materials away, vocalizing protest, engaging in problem behavior at the onset of instruction—are generally treated as non-assent indicators.

Functional assessment is essential context for interpreting assent signals. If a client's avoidance behavior has a history of producing escape from demands, that behavior may reflect escape-maintained function rather than genuine non-assent to the treatment goal. A BCBA must interpret assent signals in the context of the individual's behavioral history and the functional analysis of relevant behaviors. This complexity does not eliminate the clinical relevance of non-assent signals—it requires that they be interpreted with behavioral sophistication rather than either dismissed or acted on without analysis.

Decision trees for non-assent should be embedded in program design. When a client signals non-assent, the decision process should include: Is the behavior a reliable assent signal or likely escape-motivated? Is there a functionally equivalent procedure that produces better assent without sacrificing outcome quality? Is the teaching target itself one that the client would choose if they understood the long-term benefit? Can the delivery format be modified to improve acceptability while maintaining fidelity to the teaching procedure?

Assent assessment at the program level—asking whether the overall treatment plan reflects goals that the client would endorse given the ability to do so—requires involvement of family members, caregivers, and, to the greatest possible extent, the client. Person-centered planning approaches that incorporate client preferences and strengths into goal selection operationalize this program-level assent.

What This Means for Your Practice

Integrating assent into your clinical practice does not require a wholesale revision of your programs. It requires adding a layer of intentional observation and response to what you are likely already doing in some form. The first step is developing explicit, operationalized definitions of assent and non-assent for each client on your caseload, based on that individual's observable approach and avoidance behaviors.

The second step is making assent monitoring a formal part of your data collection. Alongside your skill acquisition data and behavior frequency counts, track session-level assent indicators—something as simple as a rating of client engagement and cooperation can be a starting point. When assent patterns change, treat that change as clinically significant information requiring program review.

The third step is revising your program design process to include assent as a criterion for procedure selection. When you are choosing between two interventions of roughly equivalent evidence support, the one that is more likely to be acceptable to this particular client should be preferred. This is not always possible, and there are situations where an effective but client-aversive procedure may be necessary—such as certain safety-related behaviors. But making acceptability a formal variable in procedure selection is a meaningful shift.

Finally, invest in communicating about assent with families and caregivers. Many families are not accustomed to thinking about their child's cooperation as a clinical variable—they may interpret a child's resistance as behavior to overcome rather than information to act on. Educating caregivers about how assent is monitored and how it influences program decisions builds the shared understanding of client welfare that good collaborative treatment requires.