A contingent order is a combination of a stop and a limit (it
can be a number of stops and limit orders combined depending on
whether your broker or market maker supports multiple order entry).
A contingent order means that a resting stop or limit order will
only become 'live' once another event, specified by the trader, has
happened.
For example, let us suppose that the FTSE is trading at a price
of 5000 and that we place an opening stop order to buy £10 per
point on a spread bet of the FTSE if the market trades at a price
of 5050. At this time we also add a contingent stop loss at a price
of 5000 and a contingent limit order at a price of 5100. Our
contingent stop and limit orders will only become 'live' once the
original buy order at 5050 has been executed. The other orders
cannot be considered to be live until the first event has taken
place.