Grease cookie sheets; set aside.
In a very large bowl, beat together butter, peanut butter, granulated sugar, and brown sugar until fluffy. Beat in eggs.
Combine flour and baking soda. Beat or stir into egg mixture. Stir in peanut butter chips.
Drop cookie dough by a level 1/4-cup measure 3 inches apart onto prepared cookie sheets.
Bake in a 350 degree F oven for about 15 minutes or until golden. Cool on cookie sheets for 3 minutes. Remove cookies to wire racks; cool completely. Makes about 32 cookies.