- • Basing psychological treatment on diagnosis can work but not always.
- • People are complicated and so are their problems.
- • Being responsive and adapting treatment plans is important.
Cognitive behavioural therapy is an evidence-based approach to helping people resolve their mental distress. Cognitive behavioural therapy practitioners are often encouraged to adapt their interventions according to the person's diagnosis. However, this approach can be too simplistic. This paper aimed to reflect on working with complex clinical presentations and to explore how transdiagnostic approaches can be effectively integrated into standard cognitive behavioural interventions. To achieve these aims, a case study of cognitive behavioural therapy assessment and treatment was presented. The interventions used are described in detail. The move away from a diagnostic-led intervention to a transdiagnostic perspective based on the individualized formulation is described. Reflections on the process are discussed and the overall approach used is evaluated with recommendations made to enhance future clinical practice.