I am writing a charting application that receives real time updates - financial quotes to be specific. I need to keep track of every quote that comes in and in the order it occurred. I get these quotes out of order, and I have to put them in order. I have used a SortedList, but found it is WAY too slow. What is the absolute fastest way I could keep track of these items and keep them sorted? The SortedList hangs up the application while it is managing incoming data - should I implement something that uses multithreading to perform the sorting?