The objective of this research plan is to develop a fully ambulatory monitoring system that includes automatic EEG abnormality detection for use in home EEG studies and sufficient data storage capability for use in ambulatory sleep studies. This plan builds upon the resultant device from the phase 1 plan, which incorporated an existing EEG seizure and spike detection algorithm from DigiTrace's predicate 110 Volt wall power system as well as integrated an OEM oximetry module into a battery-powered fully ambulatory monitor. Phase II investigations include three major refinements of the phase I technology as well as a clinical validation effort The first is to improve the existing EEG event detection algorithm to include parameters related to SPO2 oximetry and EKG measures. The second is to produce further miniaturization of the technology in order to improve patient compliance and reliability. The third is to improve data acquisition performance using 3 volt silicon technology. Finally, the resultant hardware platform and event detection scheme will be clinically validated against current standards. Over 2MM people with seizure disorders and 20MM people with sleep disorders could benefit from availability of fully ambulatory; 18 channel monitor, allowing cost effective outpatient/ alternative site patient evaluation.