A tremendous amount of data suggest that near-normal glycemic control prevents or delays complications of diabetes, which has led to a dramatic increase in continuous subcutaneous insulin infusion (CSII) or insulin pump use. In this article, the data supporting CSII in type 1 diabetes is reviewed, and the advantages and disadvantages of CSII are analyzed. In addition, CSII use in specific situations is examined, including during childhood and pregnancy and while exercising. The published articles suggest that CSII provides better glycemic control than does conventional therapy and comparable to or slightly better control than multiple daily injections. The use of CSII may be especially indicated during pregnancy or for preconception care and for diabetes presenting in childhood or adolescence.