One of the goals of the 1999 International Conference on Low-Level Radiation Injury and Medical Countermeasures was to review current and anticipated capabilities for measuring the quantity and quality of radiation exposures using personal dosimetry systems, fieldable spectroscopy equipment, and modeling strategies. Technological advances in these systems need to be evaluated for use in radiation exposure assessment. The conference focused on the application of these systems to military operations, emphasizing their use for radiation exposure assessment internationally. Capability exists to provide precise assessment of external dose during military operations, but consideration must be given to the deployability and practicality of providing additional gear for military personnel. Assessment of internal dose in the field continues to be a problem, as there are no current methods to rapidly assess intake or to account for resuspension of radioactive material due to the operation itself. Modeling can assist in overcoming confounding factors such as source-dependent energy deposition and decay, shielding, and radioisotope distribution.