In light of the increasing need by decision makers for a method of evaluating genomic applications based on the weight of evidence for their efficacy, several agencies have developed systems of classification. Here I review the horizon-scanning method for prioritizing genomics applications as described by Dotson et al. in this issue of CPT. Using the examples of the authors' Tier 1/Green classification for KRAS and Tier 2/Yellow for TPMT, I discuss differences between the guidelines issued by the Clinical Pharmacogenetics Implementation Consortium (CPIC) and those by the National Comprehensive Cancer Network (NCCN). Additionally, I offer suggestions regarding classification of the Tier 3/Red genomics applications and the reproducibility of the data-curating algorithm of the horizon-scanning method.