The peritoneum is a cavity which has been successfully utilized by nephrologists to perform peritoneal dialysis (PD) in patients with renal failure. The physiologic characteristic of the peritoneal cavity not only helps remove toxic metabolites from the body, but also provides a useful portal of entry in the body for several pharmacological agents. Several medications such as antibiotics are given via the intraperitoneal (IP) route in PD patients to treat episodes of peritonitis. More recently the IP route has been used for chemotherapy in patients with intra-abdominal malignancies, i.e. gynecological and gastrointestinal cancers and has shown very promising results. In patients with peritoneal surface malignancies, perioperative IP chemotherapy has been used with good results. The rate and amount of drug transfer in the peritoneum are dependent on several factors. Factors such as peritoneal inflammation, surface area, peritoneal blood flow, time of contact, etc, influence the drug transfer. This review discusses the usefulness of IP drug therapy and the factors influencing it, as well as strategies to increase the efficacy, and conclude that IP route is an alternate route to the more conventional drug delivery routes, and can be successfully used when the target is within the peritoneal cavity or adjacent tissue.