 This research is being done to find out whether subjects previously treated with the implantable insulin pump IIP therapy, and now taking insulin by injection, will benefit from re-implantation of IIP. The investigators will see if IIP causes more stable control of blood sugar, with fewer highs and lows. People with type 1 diabetes previously implanted with the MiniMed Implantable Pump MIP model 2000 at Johns Hopkins may join this study. 