This is a Sources Sought notice for market research to identify qualified laboratories capable of performing blood toxicology assays for a VA study. The work involves analyzing approximately 1,494 blood samples over a base period plus two option years to measure buprenorphine and norbuprenorphine levels using GC-MS or LC-MS/MS. Performance will occur at the vendor's site, which must be CLIA-certified, and the contractor must provide a secure web portal for data reporting and management. The primary contractor must have direct experience in these services and perform more than just administrative functions.