A critical aspect of sharing data is an understanding of the maturity or quality of the data. Representatives from the collaborating agencies of the NKI Signature Initiative have developed a nomenclature for communicating the maturity of data. Analogous to Technology Readiness Levels, the Data Readiness Levels provide a shorthand method for conveying coarse assessments of data from experiments or model predictions for use in improving analytical methods and validating or calibrating models, and for comparisons with legacy datasets. Data Readiness Levels (DRLs) are seven graded definitions (0-6) of data quality and data maturity. DRLs provide common, simple descriptors of data quality and maturity. Unlike Technology Readiness Levels (TRLs), DRLs are augmented with metadata qualifiers that enable further assessment, reproduction, or use of the data by others. Metadata vary by discipline, as well measurement or computational considerations. The use of both DRL levels and metadata qualifiers provide a common basis for a peer-reviewed “literature” to support informed data sharing, to augment data citation in print publications, and to accelerate the translation of research to design and manufacture.