What is Complex Trauma? How We Think About Diagnosis in the Tavistock Trauma Service

Complex trauma refers to the long-term psychological impact of repeated, relational experiences of threat, neglect, or abuse, especially during childhood. Unlike a single traumatic event, complex trauma tends to occur over time and in environments that are meant to be safe, such as within families, schools, or care systems. Its effects can be far-reaching, shaping how a person relates to themselves, others, and the world around them.

At the Tavistock Trauma Service, we meet many people whose histories are shaped by complex trauma, often beginning in childhood and compounded by further adversities in adult life. Often, people have spent years in contact with mental health services, collecting diagnoses that don’t fully capture the depth or origin of their distress. Our work begins by asking not what’s wrong with you, but what has happened to you and how those experiences live on in people's minds, bodies, and relationships.

Understanding Complex Trauma

The term complex trauma is increasingly used to describe the long-term impact of early, repeated, and relational trauma, particularly when it occurs in the context of caregiving relationships. This might include emotional neglect, physical or sexual abuse, or growing up in a household marked by fear, shame, or instability. Often, these early experiences shape a person’s internal world in ways that make safety, trust, and emotional regulation extremely difficult in later life.

While Complex PTSD (or C-PTSD) is now formally recognised in diagnostic systems like the ICD-11, it’s still under-recognised in many settings. Instead, people with complex trauma histories are often given other diagnoses, such as borderline personality disorder, anxiety, depression, or somatic symptom disorders. While these may reflect aspects of their experience, they don’t always capture the whole picture.

Why Trauma Can Go Unnoticed

Many of the people we see in our service have long histories of contact with mental health services. Some have felt helped, but many have felt unseen, misunderstood, or even further harmed. Repeated brief interventions, crisis-focused care, or rigid assessments have often left people feeling labelled but not truly listened to. Often, traumatic histories have not been given the space to be heard with someone trained to hear.

One reason for this is that trauma doesn’t always present in ways that fit easily into existing psychiatric categories. Trauma is not just about flashbacks or nightmares, as people might imagine in the classic post-traumatic stress disorder diagnosis. Importantly, it can show up in a person’s relationships, in the way they experience their body, in how they speak or fall silent, in how emotions arrive and are coped with. It can be hidden behind self-blame, dissociation, chronic pain, substance use, or shame.

A way that we have come to think about aspects of traumatic presentation in the Tavistock Trauma Service is through a series of common constructions about the way someone has configured their way of coping with traumatic distress:

• Shut Down. Some people present as emotionally shut down. They avoid contact and try to ignore feeling states. They can be quiet, highly anxious, and avoidant of relationships or even very small points of connection.

• Activated. Other people are more emotionally overwhelmed, their feelings are flooding them constantly, and they are often in a heightened state of emotional activation and arousal. They can be full of intense feelings, perhaps prone to self-harm or sudden shifts in mood.

• Somatic. Often, people hold large sites of trauma within their bodies with long-standing physical symptoms but little conscious connection to emotional pain.

• Dissociation. This is both a defensive operation within the mind, but also a way someone's personality can become more deeply structured due to extreme levels of abuse. This can present as people slipping in and out of different self-states, or experiencing parts of the self as fragmented.

  
  

  None of these presentations is pathological in itself; each is an adaptation to overwhelming experience.

A Psychoanalytic Approach to Trauma

From a psychoanalytic perspective, trauma lives on not only in symptoms but in relationships, both internally and externally, including within the therapeutic relationship. We pay attention to how early experiences are unconsciously repeated or re-enacted in the therapy room. Often this shows up in subtle ways: a difficulty making eye contact, a fear of getting too close, or a wish to please the therapist at all costs. Sometimes it appears more dramatically, in sudden ruptures and conflicts, a withdrawal and avoidance, or an extreme return to destructive ways of being.

Behind every 'resistance' to therapy lies a story to be understood, a story that may not yet be fully articulated in words. When we work psychoanalytically, we begin to see what is enacted, repeated, and unconsciously communicated. It helps us to slow down, stay curious, and hold the complexity of what is being relived and reworked in the therapeutic space. It requires us to stay attentive to how trauma unconsciously repeats itself in relationships.

At the same time, we also recognise the importance of the broader context. Many of our patients live with instability around housing, finances, or physical health. Many carry the intergenerational impact of trauma, racism, or displacement. Good psychotherapeutic work means we must always try to meet people where they are: not only psychologically, but practically and socially, and to offer a space that feels safe enough for something new to emerge. Working in a trauma-informed psychoanalytic way requires a constant interplay for the therapist, a constant negotiation internally at points of intersection and divergence.

Thinking Beyond Diagnosis

While diagnosis can sometimes be helpful, especially when it validates someone’s experience or connects them with support, it is not our primary focus. We do not gatekeep access to our service based on diagnostic criteria. Instead, we begin with a consultation, asking two simple questions: Can this patient and therapist work together? And what kind of therapeutic journey would best support this person’s needs?

This might involve individual psychoanalytic therapy, group work, EMDR, art therapy, or a combination of different approaches, all held within a trauma-informed, relational framework. Crucially, we do not expect people to be “ready” for therapy in a particular way. We understand that stabilisation, safety, and trust are not preconditions for therapy but part of the work itself.

Holding the Complexity

Working with complex trauma is never linear. It involves attending not only to symptoms but to meaning, to context, and to the deep emotional wounds that often remain hidden, even from the person themselves. It asks something of the therapist, too: to stay present, to tolerate uncertainty, and to work within a network of support that includes colleagues, teams, and patients themselves. What we offer, ultimately, is not a cure but a relationship — one that can support the slow, painful, and often courageous work of mourning, remembering, and re-finding a sense of self in the aftermath of trauma.

Further Reading

If you're curious to explore more about the ideas touched on in this post, you might find these helpful:

• What is Psychodynamic Therapy?

• Do you need a diagnosis to start therapy?

• What is Psychotherapy?

About the Author

I'm a trauma-informed psychodynamic psychotherapist working in the Tavistock Trauma Service, and a private practice in Hackney, East London, and online. I am a member of the British Psychoanalytic Council (BPC) and abide by their codes of ethics. I hold a Master’s degree with distinction and am a Clinical Fellow of the Neuropsychoanalysis Association, as well as a registered member of the British Association for Counselling and Psychotherapy (BACP)