The dengue viruses (DENV) are mosquito-borne flaviviruses which cause a spectrum of clinical disease known as "dengue," and have emerged and re-emerged as a significant global health problem. It is estimated more than 120 countries currently have endemic DENV transmission, 55% of the world's population is at risk of infection, and there are between 70-500 million infections of which 2.1 million are clinically severe resulting in 21,000 deaths annually. By all estimates the global dengue problem will continue to worsen due to the increasing mobility of the population, ecological changes, and the inability to effectively sustain vector control. There are no licensed antivirals or vaccines to treat or prevent dengue. The development and widespread use of a safe and efficacious dengue vaccine is required to significantly reduce the global dengue burden. In this review the authors discuss dengue vaccines currently in the pre-clinical and clinical development pipeline.