The INTERMED has been developed to score biopsychosocial case complexity and care needs. In this study, the interrater reliability of the INTERMED was assessed by calculating the agreement of two independent raters, based on the same information. Forty-three in- and outpatients with varying somatic complaints were double scored by a psychologist and a psychiatric C-L nurse. Correlations between total scores of the two raters were ranging from 0.91-0.96. On item level, in 83% there were no differences between the raters, in 16% there was a 1-point difference and in 1% a 2-point difference. Based on a cut-off score of 20/21, a constant k of 0.85 was found. We concluded that the two experienced raters had a high agreement, and that after sufficient training the INTERMED can be reliably scored. Its utility in improving health care delivery for patients with complex biopsychosocial care needs still has to be demonstrated.