Minimizing the risk of antibiotic resistant organisms and antibiotic residues in dairy and dairy beef products is a topic of nationwide interest. However, to design an effective outreach program on judicious use of antibiotics, it is imperative to describe the actual practices on dairies. Thus, our objective was to summarize management and treatment practices for mastitic cows on 15 California dairies as a first step in that outreach effort. Herds ranged in size from 600 to 9,500 cows. Data were collected by 2 bilingual veterinarians during the milking of mastitic cows, based on cow-side observation and responses from dairy employees. Cows identified with mastitis were kept in the same pen (n = 1) or moved to the hospital pen (n = 14). The hospital pen housed mastitic cows (n = 5); mastitic, sick and lame cows (n = 3); or mastitic, sick, lame and fresh cows (n = 6). Four of the 10 herds housing mastitic and non-mastitic cows in the hospital pen did not clean milking units in between cows. Five dairies were fitted with a milking parlor just for fresh and mastitic cows. Dairies with a single parlor milked the mastitic cow pen last. Mastitic cows were identified during regular milking based on quarter inflammation (n = 2) and quarter inflammation and milk appearance (n = 13). Two dairies used California Mastitis Test (CMT) for confirmation. Cows with abnormal milk were sampled as soon as they were identified (n = 2) or after they were moved to the hospital pen (n = 8). Milk culture results were used for selective treatment of mastitis (n = 4). The first treatment options were intramammary cephapirin [1 d (n = 1), 3 d (n = 2), 4 d (n = 1) or 5 d (n = 1)], ceftiofur [2 d (n = 1), 3 d (n = 4) or 4 d (n = 3)], hetacillin [3 d (n = 1)] or intravenous oxytetracycline and sulfamides [5 d (n = 1)]. If after treatment completion cows showed abnormal milk (n = 13) or positive CMT (n = 2) the antibiotic therapy was continued with the same (n = 10) or a different (n = 5) drug. Milk culture was used on some dairies as a treatment decision tool. Although the antibiotic drug of choice was similar across dairies, the length of treatment varied widely across dairies.