1. In a mixing bowl, cream butter and sugar; add eggs.
2. Combine flour and baking soda; add to the creamed mixture alternately with 1/3 cup of lemonade concentrate. Mix well.
3. Drop by rounded teaspoonfuls onto ungreased baking sheets. Bake at 400 degrees for 8 minutes. Remove to wire racks. Brush with remaining lemonade concentrate; sprinkle with sugar. Cool.