Traditionally, heparin-lock solution has been used with all central venous catheters. The introduction of new technology calling for the elimination of heparin and the growing concerns about the use of heparin have caused many health care professionals to question its continued use for this purpose. This literature review attempts to answer the most common questions using available research; however, there continues to be more questions than answers. At present, it appears that some farm of anticoagulant will produce more patent catheters, and heparin-lock solution is the only product commercially available. This situation drives the need for a careful assessment of patients' needs prior to abandoning the use of heparin.