C#: Random selection of elements in a list, with no repeats

Following code snippet shows how we can randomize selection of element in a list in effective manner:

System.Collections.Generic.List intList = new System.Collections.Generic.List();
intList.Add(1);
intList.Add(2);
intList.Add(3);
intList.Add(4);
intList.Add(5);

int size = intList.Count;
while (size>0)
{
size--;
int index = (new Random()).Next(0,size);
int elem = intList[index];
intList[index] = intList[size];
Console.WriteLine(elem.ToString());
}