The class Pezizomycetes is monophyletic within the subdivision Pezizomycotina. The main distinguishing character of this class is operculate asci, although in some taxa this character has been lost. The circumscription of the families and generic level delimitation in Pezizomycetes is still controversial, although several molecular phylogenetic studies have been published on this group. This paper reviews 21 families of Pezizomycetes including five new families, which are introduced here, viz. Kallistoskyphaceae, Pseudombrophilaceae, Pulvinulaceae, Strobiloscyphaceae and Tarzettaceae. Moreover, this study provides a modified backbone tree based on phylogenetic analysis of five combined loci. Descriptions and illustrations of representative taxa for the families are provided from collections made in China, Thailand and the UK, herbarium material from international herbaria (FH, FLAS, H, HKAS and MA) and the literature. Pezizales separates into six major clades. Clade 1 of Pezizales includes the families Ascobolaceae and Pezizaceae. Clade 2 is the new family Kallistoskyphaceae. Clade 3 comprises the families Caloscyphaceae, Karstenellaceae and Rhizinaceae. Clade 4 represents the families Discinaceae, Helvellaceae, Morchellaceae, Tuberaceae and Underwoodia columnaris lineage. Clade 5 includes Chorioactidaceae, Sarcoscyphaceae and Sarcosomataceae and Clade 6 comprises Ascodesmidaceae, Glaziellaceae, Otideaceae, Pseudombrophilaceae, Pulvinulaceae, Pyronemataceae, Strobiloscyphaceae and Tarzettaceae. New sequence data belonging to ITS, LSU, SSU, TEF, RPB2 gene regions from 40 pezizalian species are provided here. The paper provides a working document for apothecial Pezizomycetes which can be modified as new data comes to light. It is hoped that by illustrating taxa we provide stimulation and interest in the operculate discomycetes, so that further research is carried out on this remarkable, but poorly studied group of fungi.