Nucleotide sequence data was obtained for approximately 150 representatives of Ericaceae, Monotropaceae, Pyrolaceae, Epacridaceae, and Empetraceae. Taxa were chosen to represent the range of morphological variability, geographic distribution, and taxonomic complexity within the group. Sampling for DNA sequencing was coordinated with the morphological sampling. Approximately 90 taxa were sampled for rbcL, 120 for matK, and 60 for a combined matK - rbcL analysis. In addition, analysis of nr18s and nrITS data was performed for selected photosynthetic and non-photosynthetic taxa within the ericads. Parsimony analysis results indicate that Enkianthus is sister to the remaining ericads. Early branching lineages within ericads are: pyroloids, including three clades - two monotrop and one Pyrola-Chimaphila clade, and arbutoids. The remaining ericads form a monophyletic group that is also supported by the morphological character of anther inversion early in floral development. Within this large group the following major clades are well-supported (parsimony jackknife): Ericoideae, including Ericeae (Daboecia, Calluna, Erica), Empetreae, and Rhodoreae; Epacridoideae, and Vaccinioideae. A new classification is based on the results of the molecular and morphological analyses.

Key words: cladistics, classification, Ericaceae, molecular