In a mixing bowl, cream together the butter and brown sugar until smooth.
Beat in the eggs one at a time, then stir in the vanilla.
Combine the flour, baking soda, and salt; gradually stir into the creamed mixture.
Drop by rounded spoonfuls onto ungreased cookie sheets.
Bake for 8 to 10 minutes in the preheated oven, or until edges are golden. Allow cookies to cool on baking sheet for 5 minutes before transferring to a wire rack to cool completely.