The north Andean region, which includes Colombia, Ecuador, and Peru, has perhaps the richest flora in the world and is the center of diversity of the family Araceae. The low to middle elevation wet forests of the area abound with aroids which cover the ground, climb up tree trunks, and as epiphytes adorn the outer branches of the trees. Many of our finest ornamental aroids, including Anthurium andreanum, A. crystallinum, Caladium bicolor, and Philodendron erubescens, are derived from this area. The purpose of this paper is to provide a key and brief descriptions of the genera of Araceae of the northern Andes which should enable anyone to identify to genus aroids from the region. The key is also applicable in Central America, but only partly so in the rest of South America where a number of additional genera, principally of the subfamily Aroideae, are found.