Potential participants will be pre-screened with the inclusion criteria for eligibility. The informed consent process will begin for those participants who have been determined to meet the inclusion criteria. After the potential participant's signed consent has been provided, further evaluations for eligibility will be performed (e.g., there are several medical and physical exclusion criteria). Those potential participants who meet both the inclusion and exclusion criteria will be eligible to enroll into the ReWalk-I study. Baseline evaluations and personalized measurements for fitting to the ReWalk-I will be performed over one week, before the training sessions begin. The ReWalk sessions will consist of a Learning Phase (12 sessions in 4 weeks) and a Training Phase (18 sessions in 6 weeks). These times may vary by each participant's ReWalk learning curve. Training will begin with sit-to-stand, stand-to-sit, and standing balance activities. Progression to walking will occur as skills advance. Each session will be an average 50 minutes, with 3 sessions per week. The skills to be learned include 1) sit-to-stand, 2) stand-to-sit, 3) 2-arm standing balance, 4) 1-arm standing balance, 5) walking, and 6) stair climbing. The study evaluations will be repeated after the Learning Phase, after the Training Phase and 1-month post training follow-up.