A method for quantitative biopsy cultures of burn wounds has been developed and evaluated. Specimens are obtained by full-thickness biopsy of the burn wound using a scalpel. Specimens are processed by maceration, suspension in physiologic saline solution, and plating of serial dilutions of the suspension on appropriate media. Quantitative counts are performed and expressed as the number of bacteria per Gm. of burn-wound tissue. Experience with this technic in the care of 210 consecutive patients with burns of more than 20% total body surface area has shown it to be more reliable than surface-culture technics. Patients were considered to have wound colonization when 104 or more organisms per Gm. of burned tissue were recovered from different areas of the body. Appropriate antibiotic therapy was instituted on the basis of these results. Routine use of this method was found to be effective, simple, and practical as an aid in the early diagnosis of sepsis in the burned patient.