The purpose of the study was to determine whether peer education using group approach focusing on knowledge and practice aimed at improving the insertion and management of peripheral intravenous catheter and procalcitonin detection could decrease the rate of peripheral intravenous catheter- related blood stream infections and associated complications. . Subjects and Methods: This study was conducted during nine months from January 2010 to September 2010 in medical, surgical, neurology, and orthopedic departments at Mansoura University Hospitals. Two categories of subjects were included in the study; A- Nurses, including (8 peer trainers, were selected based on certain criteria and 60 trainees). B-130 Patients.Three research tools were used in the study: 1-Nurses' Knowledge questionnaire regarding the insertion and management of peripheral intravenous catheter and peripheral intravenous catheter- related blood stream infections and associated complications.2- Nurses' practice checklist regarding the correct procedures for the insertion and management of peripheral intravenous catheter, and 3-Surveillance of patients with peripheral intravenous catheter- related blood stream infections and associated complications. Results: There was a significant increase of peer trainers and trainees 'knowledge and practice in all items before and after training (p<0.05) .There was a significant reduction in the percentage of infections in the surgical and Medical departments (p value was < 0.001 and 0.009) while there were no significant reduction in the percentage of infections in both neurosurgery and orthopedic departments. The total isolated organisms from PCABSI were 61 microorganisms most of them were Gram negative .Detection of procalcitonin by EIA showed that there was significant high level among patients with Gram negative bacterimia versus patients with Gram positive and also patients with candidal bacterimia (P-value < 0.001). Limitations for the study: This study was based only on peer trainers and trainees of Mansoura University hospitals, so, findings can not be generalized for peer trainers and trainees of all university hospitals. Conclusion: Based on the findings of this study, peer education program and procalcitonin detection was found to be effective in improving knowledge and practices of both trainers and trainees, reduction in the percentage of infections in the surgical and medical departments and no significant reduction in the percentage of infections in both neurosurgery and orthopedic departments. Recommendations: Training for peer educators needs to be an on-going process; refresher and more advanced training should be offered periodically. Retesting study should be done on a larger sample using a control group. A follow-up study could describe the aspects of the relationship that seem important from both the trainers and the trainee's perspective, this data could be used to further refine effective teaching and learning protocols. More research is necessary to assess long-term impact evaluations. A broader study across several health institutions is also recommended so as to get a sample that will be the best representative of all nurses' level could reduce morbidity and the costs of care associated with catheter-related bloodstream infections.It is hoped that this study will help in planning and improving policies for addressing issues related to the insertion and management of peripheral intravenous catheter at Mansoura University hospitals.