The goals of this guidance are to outline the infrastructure and expertise needed to develop laboratory capacity for a biomonitoring program and to highlight some of the main considerations chemists should address before beginning a biomonitoring study, which include the need to: ' Define the goals of a biomonitoring study; ' Choose the appropriate biomarker in the appropriate matrix at a sufficient level of sensitivity; ' Identify resource needs and sources of potential funding; ' Collaborate with epidemiologists and toxicologists in the development of the study design and to analyze and communicate biomonitoring data; ' Produce reliable, valid and comparable data; ' Engage the community early in the study design process; and ' Develop an effective communication plan that involves reporting of individual results (if appropriate), aggregate data and access to public health, citizens or medical professionals for results distribution and interpretation.