Dear Professor. Thank you for asking me to edit your interesting paper. I have made a number of changes to make sure all grammar is correct and so that the paper is clear and readable, without changing your meaning.<br />I looked up the title to Mr. Porter's work and corrected it at the top of your paper.<br /><br />Regarding your further additions to the paper, as a non-economist who has not read Porter's work, I cannot make many helpful suggestions. As a reader, I think it would help to elaborate on each of his four determinants, especially the Factor Conditions and the Demand Conditions. I think it would help to add some examples under the section on Firm Strategy, Structure and Rivalry. (In the section on Factor Conditions, I wasn't sure if the first sentence reflects Porter's views, or the views of Smith and Ricardo which Porter disputes).<br /><br />Good luck with your paper!