The taxonomic classification of 182 phenotypically similar isolates was evaluated using DNA-DNA hybridization and 16S rRNA gene sequence analysis. These bacterial isolates were mainly derived from clinical sources; all were Gram-negative non-fermenters and most were indole-producing. Phenotypically, they resembled species from the genera Chryseobacterium, Elizabethkingia or Empedobacter or belonged to CDC groups IIc, IIe, IIh and IIi. Based on these analyses, four novel species are described: Chryseobacterium bernardetii sp. nov. (type strain NCTC 13530(T) = CCUG 60564(T) = CDC G229(T)), Chryseobacterium carnis sp. nov. (type strain NCTC 13525(T) = CCUG 60559(T) = CDC G81(T)), Chryseobacterium lactis sp. nov. (type strain NCTC 11390(T) = CCUG 60566(T) = CDC KC1864(T)) and Chryseobacterium nakagawai sp. nov. (type strain NCTC 13529(T) = CCUG 60563(T) = CDC G41(T)). The new combination Chryseobacterium taklimakanense comb. nov. (type strain NCTC 13490(T) = X-65(T) = CCTCC AB 208154(T) = NRRL B-51322(T)) is also proposed to accommodate the reclassified Planobacterium taklimakanense.