Methods and systems related to trading engines

1. A method comprising:

(a) receiving electronic data describing a trading order;

(b) checking said data describing said trading order to determine whether a first set of pre-defined conditions is satisfied, wherein said first set of pre-defined conditions is associated with a first set of one or more trading algorithms, and determining that said first set of pre-defined conditions is satisfied;

(c) selecting with a processing system one or more first trading algorithms from said first set of one or more trading algorithms associated with said first set of pre-defined conditions, for execution of said trading order;

(d) commencing with said processing system execution of said trading order via said one or more selected one or more first trading algorithms;

(e) checking with said processing system, during execution of said trading order via said selected one or more first trading algorithms, status of said trading order and said first set of pre-defined conditions;

(f) if said first set of pre-defined conditions is no longer satisfied, checking whether a second set of pre-defined conditions is satisfied; and

(g) if said second set of pre-defined conditions is satisfied, switching with said processing system execution of said trading order to one or more second trading algorithms selected from a second set of trading algorithms associated with said second set of pre-defined conditions;

wherein said processing system comprises one or more processors.

2. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to parameters of trading orders.

3. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to current market conditions.

4. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to trading patterns of a market participant placing said trading order.

5. A method as in claim 1 , wherein said step of associating said one or more trading algorithms with said trading order comprises checking a plurality of sets of pre-defined conditions that have been arranged in a hierarchical order of priority.

6. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to minimum or maximum measurements of available liquidity.

7. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to absolute momentum.

8. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to relative momentum.

9. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to a spread measurement.

10. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to side of said trading order.

11. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to size or change in size of said trading order.

12. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to identity of a market participant placing said trading order.

13. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to whether order execution has been switched from said selected one or more first trading algorithms.

14. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to whether a specified execution speed of said trading order has been changed.

15. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to how much time has elapsed since said trading order was placed.

16. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to a change in type of order for said trading order.

17. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to what percentage of said trading order has been filled.

18. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to a measure of market impact or projected market impact of said trading order.

19. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to whether there has been recent news related to a security related to said trading order.

20. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to a securities sector for a security related to said trading order.

21. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to trade history for a security related to said trading order.

22. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to a portfolio of a market participant placing said trading order.

23. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to a measurement relative to a benchmark.

24. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to a measurement of volatility.

25. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to an analysis relative one or more exchange traded funds and/or indexes.

26. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to whether said trading has been canceled or replaced.

27. A method as in claim 1 , wherein one or more of said set of pre-defined conditions relate to identity of a portfolio manager placing said trading order.