Important characters in the classification of the lichenized familyAlectoriaceae (Lecanorales) are discussed and evaluated. A few associated genera presently accommodated in the familyParmeliaceae (Lecanorales) are also discussed. Characters in the asci and hamathecium are of major importance, but structural characters such as general thallus organization and anatomy of cortical layers must also be considered. Secondary chemical products, however, were not found to be decisive for the circumscription of this family. Only three genera, Alectoria, Oropogon, and Sulcaria, can be included, based mainly on the structure of the large, strongly amyloid asci; the rather large and darkly pigmented, thick-walled spores, usually few per ascus; and the structure of the anastomosing paraphysoids. Arguments are also given as to why the other alectorioid genera, i.e. Bryocaulon, Bryoria and Pseudephebe must be excluded from this family. Similarly developed ascus and hamathecial structures are also discussed in a few unrelated parmelioid genera: Cetrelia, Menegazzia, Parmelaria, and Parmelia.