The term "Significant Properties" has been given a variety of definitions and used in various ways over the past several years. The relationship between Significant Properties and the OAIS term Representation Information has been a puzzle. This paper proposes a definition of Significant Properties which provides a way to clarify this relationship and indicates how the concept can be used in a coherent way. We believe that this approach is consistent with the actual use of the concept and does not invalidate the previous pieces of work but rather provides a clear and consistent view of the concept. It also links together Authenticity and Provenance which are also key concepts in digital preservation.