Preheat oven to 375 degrees F (190 degrees C). Grease cookie sheets.
In a large bowl, cream together the butter, white sugar and brown sugar until smooth.
Beat in the eggs one at a time, then stir in the vanilla.
Combine the flour, baking soda and cinnamon; stir into the creamed mixture.
Stir in the oats.
Drop by rounded spoonfuls onto ungreased cookie sheets.
Bake for 8 to 10 minutes in the preheated oven. Allow cookies to cool on baking sheet for 5 minutes before transferring to a wire rack to cool completely.