Technical Abstract: Direct plating is an effective technique for isolation and enumeration of campylobacters from a variety of sample types: however, distinguishing campylobacters from non-campylobacter contaminants which frequently grow on many existing agars is difficult. More selective and differential agars were developed to facilitate Campylobacter enumeration by combining selective antibiotics and triphenyltetrazolium chloride (TTC). Growth of many microorganisms reduce the initially colorless tetrazolium salts to insoluble formazan compounds which impart a red color to the growing colonies. We found that exposing Campylobacter to low levels of TTC (200mg/L) was not inhibitory to growth, yet was sufficient to give a deep red/magenta color to the colonies. The new agars (Campy-Line agar [CLA] and Campy-Line Blood Agar [CLBA]) are translucent. The contrast of deep red colonies on a translucent background greatly facilitates Campylobacter isolation and makes enumeration on light boxes or by electronic means possible. Direct plating of broiler carcass rinse samples was compared on Campy-Cefex agar and CLA (n=76) or CLBA (n=61). Recovery of Campylobacter populations was not significantly different between the agars (P<0.05); however, isolation was much easier on the CLA or CLBA. Fewer than 3 non-campylobacter colonies were observed on the CLA or CLBA, whereas the Cefex agar supported the growth of between 0 and 72 contaminating cfu/ml.