Introduction <p>Treatment strategies for endometriosis have traditionally been biomedical. There is a need for a more multidimensional understanding of endometriosis and more targeted and individualized treatment interventions, including psychological approaches.</p> Methods <p>The aims of this study were twofold: (1) to identify key biopsychosocial characteristics in individuals attending a tertiary clinic for endometriosis and (2) to inform the development of future, targeted, and efficacious interventions by examining the importance of psychological processes central to two scientific models, pain catastrophizing and fear of movement from the fear-avoidance model, and psychological inflexibility from the psychological flexibility model.</p> Results <p>Psychosocial variables, more specifically perceived control and powerlessness, social support, and depression, were of particular importance to the symptom structure in this patient population. In contrast, biological factors appeared to have low relevance within this network. When aiming to inform the development of future, promising psychological interventions for endometriosis, psychological inflexibility emerged as the most important psychological process variable in the symptom network.</p> Conclusions <p>A multidimensional approach based on the biopsychosocial model appears valuable for understanding endometriosis. Treatment interventions grounded in the psychological flexibility model may hold promise for this patient population, a possibility that warrants further investigation in future studies.</p>