A multiple level security system and method for encrypting data within documents is disclosed. The method includes one or more different encryption algorithms, and can employ the one or more different encryption algorithms to achieve the multiple levels of encryption. More particularly, a first encryption algorithm is based upon multiple rearrangements of bits representing data to obtain encoded data. A second encryption algorithm is based upon performing multiple XOR operations on bits representing data so that each data word is at least encoded with previous data words. Either encryption method or a combination of both encryption methods can be repeatedly applied to portions of data within a document to selectively encrypt each data portion within the document in accordance with the authorization level associated with the data portion.