Severe hypoglycaemia leading to collapse without warning is one of the most-feared complications for those with Type 1 diabetes. The aim of this study is to determine whether detection and targeted prevention of hypoglycaemia by using either an optimised subcutaneous insulin regime or continuous insulin regime can restore hypoglycaemia awareness in Type 1 diabetes. Following a 6-day continuous subcutaneous monitor glucose profile, participants will be randomised to 1 of 3 interventions: rigorous avoidance of hypoglycaemia on current insulin regime; targeted optimisation of subcutaneous insulin regime to avoid hypoglycaemia; or continuous subcutaneous insulin infusion. Symptomatic experience and severity of hypoglycaemia, pattern of hypoglycaemia on glucose profiling and, in selected individuals, response to hyperinsulinaemic hypoglycaemic clamp, will be compared over a 6 month period. It is envisaged that successful prevention of hypoglycaemia by one or more interventions may reverse altered hypoglycaemia awareness and prevent further episodes of severe hypoglycaemia.