I'm studying Algorithmic Trading Strategies now.

I'm wondering what's the

difference between

**Agency Algorithmic Trading Strategies** and

**Proprietary Algorithmic Trading Strategies**. Can anyone give me an explanation? Any help will be really appreciated.

I have read several papers of Robert Almgren, like "Optimal Trading in a Dynamic Market", "Optimal Execution of Portfolio Transactions", where he tried to solve

a liquidation problem using dynamic programming.

And in Coggins' paper "Optimal Trade Execution: An Evolutionary Approach" where he tried to solve the trade execution problem called

Trader's dilemma using a Genetic Algorithm approach.

Are they talking about the same execution problem? Although I finished the two papers, I'm still confused. Almgren focused on order schedule (Kissell's work is also like this). And Coggins seemed to evolve an order submission strategy (limit order/ market order).

In Almgren's approach, why doesn't he consider choice of order (limit/market order), limit price, submission time?

Is Almgren's strategy an Agency Strategy? Is Coggins's strategy a Proprietary Strategy?

Is there any definition of Agency Strategy?

I do not have any work experience before. Is there any significance in the Industry to research on proprietary strategies?

Thanks a lot.