Understanding Diagnoses: Advantages and Limitations in Psychotherapy

How should a client’s diagnosis factor into the psychotherapy process? This is a question explored by clinicians, clients, and researchers alike.

Many of my adult clients with ADHD describe feeling deeply validated when they receive their diagnosis. After years of struggling with symptoms, they often feel relief in realizing that their experiences are not the result of laziness, lack of effort, or personal failure.

At the same time, diagnoses can sometimes carry unintended consequences. A person diagnosed with major depressive disorder, for example, may come to see the diagnosis as confirmation of a long-standing belief that something is fundamentally wrong with them. Some diagnoses also remain heavily stigmatized, which can affect how individuals are viewed and treated within healthcare systems and relationships.

These realities naturally raise an important question: beyond insurance billing and communication between providers, what value does diagnosis actually bring to therapy?

To begin answering that question, it helps to first understand what a psychiatric diagnosis is—and what it is not.

Many people wonder whether they have a particular diagnosis because they relate strongly to one or two symptoms listed online or described on social media. In reality, most diagnostic criteria describe experiences that many human beings have at some point in life. The difference is often not whether a person has the experience, but the intensity, frequency, rigidity, and impact it has on daily functioning.

For example, most people experience fears of rejection or abandonment at times. In borderline personality disorder, those fears can become so intense and pervasive that relatively minor events—such as a delayed text message or someone arriving a few minutes late—trigger overwhelming emotional distress, panic, anger, or despair.

Modern psychiatric diagnoses are developed through decades of clinical observation and research. Researchers examine patterns across large groups of people using interviews, behavioral data, and psychological measurement tools. Statistical methods help identify clusters of symptoms that tend to occur together, eventually forming the diagnostic criteria used in clinical settings today.

Diagnostic systems were also shaped by the growing need for consistency across the mental health field. As psychiatry evolved, clinicians needed shared language for research, treatment planning, communication between providers, and insurance reimbursement. Standardized diagnostic criteria made it easier to study mental health conditions systematically and expand access to care.

At the same time, diagnosis-based systems have important limitations. Human emotional experiences do not always fit neatly into categories, and diagnostic frameworks are inevitably shaped by the cultural and social assumptions of the time in which they are developed. Historically, the DSM and related diagnostic systems have struggled to fully account for the experiences of people from diverse cultural backgrounds, as well as individuals living in extreme poverty, unstable housing, or other forms of chronic environmental stress. Experiences that may represent understandable adaptations to trauma, marginalization, or survival can sometimes be interpreted narrowly through the lens of pathology when broader social and cultural contexts are not carefully considered.

Diagnoses can also create stigma, oversimplify a person’s life experience, or encourage individuals to view themselves primarily through the lens of illness. While diagnostic categories can be useful clinical tools, they are ultimately imperfect attempts to describe highly complex human experiences.

So how should diagnosis influence psychotherapy?

A thoughtfully developed diagnosis can help guide treatment. It may help clinicians identify therapeutic approaches that are likely to be effective, clarify which concerns should be prioritized first, and provide language that helps clients better understand their experiences. For many people, receiving a diagnosis can reduce shame and increase self-understanding.

At the same time, diagnosis should never become the center of a person’s identity or the sole framework through which a therapist understands them. A diagnosis alone does not create healing. Research consistently shows that the quality of the therapeutic relationship is one of the strongest predictors of positive outcomes in therapy, regardless of the treatment modality being used.

No one is their diagnosis. People are far more complex than any label or set of criteria. A diagnosis may describe patterns of symptoms, but it cannot fully capture a person’s history, relationships, values, strengths, or capacity for change.

Ultimately, therapy is not about reducing a person to a category. It is about understanding the unique human being sitting in the room or on the other side of the Zoom session.

Why a Functional Approach?

All behavior serves a purpose. Yes, even the behaviors that seem to sabotage our desire for improvement. In many cases, the behaviors that create the most pain are attempts to meet the most important unmet needs.

A decade ago during my senior undergrad year at UMass Boston, I sat in an early morning trauma capstone course taught by psychologist Lizabeth Roemer. We were discussing traumatic stress through a cross-cultural lens when she posed a deceptively simple question:

Two people can experience the same event. One develops post-traumatic symptoms; the other does not. Why?

The answer, of course, is context. Human experience does not happen in a vacuum. Our nervous systems, histories, relationships, environments, and beliefs shape how we interpret and respond to what happens to us.

Then she casually said something that, years later, I realized fundamentally shaped my clinical approach—especially when working with people who struggle to verbalize what they’re experiencing internally:

“If you listen to a person’s experience, their behavior makes perfect sense.”

That idea stayed with me.

When a client becomes angry and defensive in session, lashes out at their partner, sobs after receiving critical feedback at work, shuts down when asked to communicate, or spends borrowed money on scratch tickets despite desperately wanting to stop, I do not see evidence of something broken that requires fixing.

I see adaptation.

I see a person responding to their internal and external world with the tools their mind and body have learned to use. And most importantly: somewhere along the line, those behaviors worked.

To be clear, a behavior “working” does not mean it improves our lives or moves us toward the future we want. It simply means the behavior successfully fulfills a function in the moment. It reduces distress. It creates escape. It restores control. It protects against shame, vulnerability, rejection, or emotional overwhelm.

The problem is that many of these strategies come with enormous long-term costs.

This is why treatment focused only on stopping behavior often provides temporary relief before new behaviors emerge that create similar consequences. If we never understand what the behavior is doing for a person, we risk fighting the symptom while leaving the underlying need untouched.

For me, therapy is not about asking, “What is wrong with this person?”

It is about asking:

“What problem is this behavior trying to solve?”

Behind our most destructive and difficult-to-manage behaviors is often a part of us trying desperately to meet a basic human need: safety, connection, control, validation, relief, belonging, autonomy, or emotional protection.

Once we understand the need, we can begin developing ways to meet it that no longer collide with the life we want to build.

That is where meaningful change begins.