An implementation field program is the decision by EMAP to make a long-term commitment to provide scientifically defensible estimates of current status, trends, and changes in condition indicators and association of these indicators with selected stressors. The decision will include consideration of (1) the link between values and indicators proposed for implementation, (2) the scientific basis for the indictor, (3) the scientific validity of the proposed national sampling design, (4) a demonstrated ability to meet the EMAP status and trends program quality objectives, and (5) explicit plans that ensure the implementation can be conducted and produce annual statistical summaries. (New term 1993. See related: demonstration field program, demonstration project, pilot project, pilot field program.)