We assessed the predictive value of anatomical findings and karyotype for establishing a diagnostic orientation in patients with disorders of sex development (DSD). We performed a retrospective chart analysis of 228 patients, grouped into 4 categories: 46,XX DSD, non-dysgenetic testicular DSD, dysgenetic testicular DSD and ovotesticular DSD. Degree of virilisation, presence of vagina, presence of palpable gonads, size of gonads and a plain karyotype was available for all cases. 46,XX DSD due to congenital adrenal hyperplasia counted for 59.2% of the cases, non-dysgenetic testicular DSD for 13.6%, dysgenetic testicular DSD for 21.5% and ovotesticular DSD for 5.7%. Excluding congenital adrenal hyperplasia (CAH), a karyotype with at least one 46,XX cell line had a high diagnostic efficiency for ovotesticular DSD. In these patients, anatomical findings were not as useful to predict the gonadal phenotype. The existence of a 45,X cell line predicted with very high efficiency dysgenetic testicular DSD. Genital palpation was only partially helpful to predict the existence of testicular tissue. Non-dysgenetic testicular DSD could be ruled out with high efficiency in patients with an abnormal karyotype. Anatomical findings were helpful in 46,XY patients: palpated masses predicted non-dysgenetic testes with high accuracy. In all cases assessment of gonadal volume was less useful.