Protocol for the identification of single bacterial cells using DIG-labeled oligonucleotides. Includes: Organisms and growth conditions; Cell fixation and preparation of cell smears; DIG labeling of oligonucleotides with DIG-ddUTP; In situ hybridization using digoxigenin-labeled oligonucleotides; Detection of DIG-labeled oligonucleotides with fluorescently labeled anti-DIG Fab fragments; Detection of DIG-labeled oligonucleotide.