Transcranial direct current stimulation (tDCS) can be an effective therapy for stroke recovery patients. However, the extent to which patients show improvements with tDCS is highly variable. This variability may arise due to the differences of stroke location in the brain and because of differences in brain damage, all of which may differ between patients. If the relationship between these factors and tDCS efficacy were known, recovery from stroke using tDCS might become more predictable. Our overall objective is to understand potential measures of tDCS efficacy that may someday allow for optimization of clinical outcomes and patient care.