Modern Roses 12 is a comprehensive listing of all rose cultivars and species documented during the research and preparation by its editors.

"The American Rose Society has made the decision to publish two separate volumes: 'Modern Roses 12', which is a comprehensive listing of all rose cultivars and species documented during the research and prparation by its editors, and the 'Official registry of rose cultivars', which focuses on registered cultivars and their identifying details."--Preface.