Gram-negative bacteria isolated from turkeys with coryza in the United States, the Federal Republic of Germany, and the Republic of South Africa were compared with known Alcaligenes species and Bordetella bronchiseptica. The turkey isolates were separated into three distinct groups based on biochemical and physiologic tests. Forty of the 68 isolates studied (group I) were different from Alcaligenes sp. and B. bronchiseptica. Isolates in group I produced a heat-labile hemagglutinin and did not grow on Simmons' citrate agar. Isolates in group II (25 isolates) were similar to A. faecalis and A. odorans, grew on Simmons' citrate agar, and did not produce a hemagglutinin. Isolates in group III were B. bronchiseptica. Isolates from groups I and II caused coryza in poults. Group III isolates were not pathogenic.