Abstract. We call G a Hall X -group if there exists a normal nilpotent subgroup N of Gis, one in which normality is a transitive relation. We present several new local classes of groups which locally define Hall X -groups and T 0 -groups where X ∈ {T , PT , PST }; the classes PT and PST denote, respectively, the classes of groups in which permutability and S-permutability are transitive relations.