- Pitahayas, dragonfruit and vine cacti are the popular names used to describe the species belonging to the genus Hylocereus. This group of semi-epiphytic cacti is endemic to tropical regions of northern South America, Central America and Mexico. Since these plants use the Crassulacean acid metabolism (CAM) photosynthetic pathway, they present an attractive alternative for dryland agriculture as perennial fruit crops in arid and semi-arid regions. Several of these species bear large and attractive edible fruits, which are both juicy and sweet. The fruits have black small crispy seeds and either a spineless (Hylocereus species - red pitahayas) or a spiny peel (only in Hylocereus megalanthus - yellow pitahayas). Interest in these crops is continuously increasing, and they are currently cultivated on small scale in Vietnam, Mexico, Colombia, Nicaragua, Ecuador, the USA, Israel, Thailand, Japan, and Australia, with Vietnam being the most important exporter of fresh fruit. Initial domestication and introduction programs were aimed at producing the know-how for developing the appropriate agricultural techniques for profitable and sustainable cultivation of these species as fruit crops. However, despite their economic potential, these fruit crops have not received the requisite attention from the scientific community, and until recently little was known regarding cultivation, optimal agrotechniques, flowering and pollination, pests and diseases, and harvesting and shelf-life conditions. This review addresses the current breeding status, and the challenges and possible strategies for future development of these underexploited fruit crops. © 2015, International Society for Horticultural Science. All rights reserved.