An unblinded, randomized, cross-over design with each patient participating in two 40-hour outpatient admissions: (a) Experimental involving automated Control-to-Range (CTR) and (b) Control using Continuous Glucose Monitor (CGM)- augmented insulin pump treatment outside of a hospital based clinical research center. The principal goal is to validate a smart phone-based control-to-range (CTR) system for ambulatory use and to estimate the effect of CTR vs. sensor-augmented pump therapy, thereby providing justification for further larger home-based trials of CTR.