Studies were performed to develop improved methods for enumeration of Listeria monocytogenes. Both direct plating and a most probable number method (MPN) were evaluated using heat injured L. monocytogenes. Heat injured cells (56 C for 20 min) were plated on selective plating agars and enumerated. Hemolytic Ceftazidime Lithium Chloride Agar (HCLA) was found to have a much higher recovery rate of heat-injured L. monocytogenes than either Oxford (OXA), Lithium Chloride Phenolethanol Moxalactam Agar (LPM), Al-Zoreky agar, or Lithium Chloride Ceftazidime Agar (LCA). Its recovery rate was about equal to Listeria Enumeration Agar#1 (LEA#1) and Listeria Enumeration Agar#2 (LEA#2). Of three different MPN enumeration broth systems, a modification of Penn State University broth (PSU) using oxyrase to provide an anaerobic environment was found to provide the best recovery of heat-injured L. monocytogenes cells. With the direct plating method, plates were incubated for 26-30 h at 35° C. Most background microflora was suppressed with cheese and mussel samples. This method would be appropriate for samples without very high levels of competitive microflora, but the sensitivity is lower than an MPN method, as a cell level of 10/g is needed before colonies will be expected on the HCLA plates.