The sequential monolayer-suspension culture technique has been used in over 800 samples during the period from January 1, 1990 till December 31, 1999. Patients were referred from all over Belgium. The culture technique was successful in 75% of the samples. In 85% of the patients a final conclusion regarding the exclusion/diagnosis of primary ciliary dyskinesia was made. In a total of 84 patients (10.3%) the final diagnosis was primary ciliary dyskinesia. Eighteen percent of the samples were considered normal, in 24% secondary ciliary dyskinesia was diagnosed.