The Zingiberales are a tropical group of monocotyledons that includes the bananas, gingers and their relatives. The phylogenetic relationships among the currently recognized eight families are investigated here using parsimony and maximum likelihood analyses of four character sets: 1) morphological features; and sequence data of the 2) chloroplast rbcL gene; 3) chloroplast atpB gene; and 4) nuclear 18S rDNA gene. Outgroups for the analyses include the closely related Commelinaceae + Philydraceae + Haemodoraceae + Pontederiaceae + Hanguanaceae as well as seven more distantly related monocots and paleoherbs. Only slightly different estimates of evolutionary relationships result from the analysis of each character set. The morphological data yield a single fully resolved most parsimonious tree. None of the molecular data sets alone completely resolves interfamilial relationships. The analyses of the combined molecular data set provide more resolution than individual genes and the addition of the morphological data provides a well-supported estimate of phylogenetic relationships: (Musaceae ((Strelitziaceae, Lowiaceae) (Heliconiaceae ((Zingiberaceae, Costaceae) (Cannaceae, Marantaceae))))). Evidence from branch lengths in the parsimony analyses and from the fossil record suggest that the Zingiberales originated in the early Cretaceous and underwent a rapid radiation in the mid-Cretaceous by which time most extant family lineages had diverged.