A total of 154 Burkholderia cepacia complex strains, isolated from cystic fibrosis and non-cystic fibrosis patients and the environment, representing all nine genomovars and a putative tenth, were analysed by 16S rDNA-restriction fragment length polymorphism using the restriction enzymes AluI, CfoI and DdeI. Examining this diverse strain collection resulted in very diverse restriction patterns. Only B. cepacia genomovar VI could be identified unambiguously. The same restriction patterns were observed for B. cepacia genomovars I and III and approximately half of the Burkholderia ambifaria, B. anthina and B. pyrrocinia strains. Burkholderia vietnamiensis and B. ubonensis, a putative tenth B. cepacia complex genomovar, shared identical restriction profiles. The majority of Burkholderia multivorans and B. stabilis isolates generated a unique restriction pattern, but two strains of each showed divergent restriction profiles which were also observed in other genomovars. ß