High Dose Methotrexate (HDMTX) is an integral part of osteosarcoma therapy whose main toxicities include myelosuppression, mucositis, nephrotoxicity, and hepatitis. In order to deliver HDMTX therapy safely, patients require urinary alkalinization, hydration, monitoring of renal function, therapeutic drug monitoring, and leucovorin rescue. Due to the required supportive care needs, HDMTX has historically been given as an inpatient. In some centers however, HDMTX is being given safely as an outpatient in order to reduce health care costs, improve patient quality of life and to deliver timely therapy with limited inpatient chemotherapy beds available.