This document describes the standard procedures required to perform intravenous catheter insertions and intravenous sampling by trained technicians/ phlebotomists. This SOP is only a supplement to regular training; technicians/ phlebotomists need to have hands-on training and sufficient experience before performing these procedures with study participants. These procedures are specific to the Department of Human Health and Nutritional Sciences (HHNS) and should only be used by approved and trained HHNS phlebotomists.