Context:Rapid treatment of sepsis is of crucial importance for survival of patients. Specific and rapid markers of bacterial infection have been sought for early diagnosis of sepsis. One such measurement, Procalcitonin (PCT), has recently become of interest as a possible marker of the systemic inflammatory response to infection.Aims:This study was done to find out the common sources of sepsis and to evaluate the diagnostic value of PCT, its predictive value and its relation with Sepsis-related Organ Failure Assessment (SOFA) scores and mortality in various stages of sepsis.Settings and Design:The prospective study was conducted at our tertiary care center from October 2006 to December 2008. A total of 100 patients were included in the study. The study sample included all patients aged above 18 years presenting consecutively to our center during the study period with acute sepsis. They were divided into three groups: sepsis, severe sepsis and septic shockbased on standardized criteria.Materials and Methods:PCT and various other relevant factors were measured in all study subjects. These parameters were compared among the three study groups. The statistical analyses were done using Student “t” test and two-way analysis of variance (ANOVA).Results:Respiratory tract infection was the most common source of sepsis. PCT proved to be an excellent indicator of sepsis with sensitivity of 94%. There was a significant association between serum PCT and SOFA scores (P < 0.05). Serum PCT levels did not predict mortality in the present study.Conclusions:PCT is among the most promising sepsis markers, capable of complementing clinical signs and routine lab parameters suggestive of severe infection.