A well-known theorem of P.
Hall states that a finite group G is solvable if, and only if G possesses a complete set
of permutable Sylow subgroups. Our goal here is to investigate finite (solvable)
groups whose Sylow subgroups are related by a normalizer condition (N). The
presence of property (N) for a group G implies that G has slructure similar to a
Sylow tower group.