Abstract. SOA proposed security mechanisms are only centered in the data transmitted between service provider and consumer. However, it's well known that the biggest threats to the integrity of the information are precisely focused not on the data directly but on the code that manages it. Our main statement is that it will only be possible to reach an acceptable level of security if the protection mechanisms cover not only the data but also the code that process these data. In this paper we present a new approach about mobile code security based on the Services Oriented Architecture Reference Model and Web Services technology. This new model allows the development of systems with end-to-end security, where all elements (code and data) are secure.