Sablefish have a wide distribution in the Pacific Ocean extending from Mexico to Alaska and through the Aleutian Islands and Bering Sea. Studies that have been completed on stock structure of this species have been inconsistent. We are involved in a project to define the genetic stock structure of sablefish populations in the northern Pacific Ocean. Sablefish have been sampled across their range using NOAA groundfish surveys and restriction site associated DNA (RAD) sequencing will be used to identify single nucleotide polymorphisms (SNP) in these samples. SNPs will be analyzed to evaluate the genetic relationship of sablefish across their range and to identify possible SNPs under selection in these populations.