Abstract: WEB commerce security is an important issue that has been leading to negative or adverse effects on the further development and growth of WEB-commerce. We discuss objectives such as security goals integrity, confidentiality, availability and we discussed the security services and how these are related to the three security goals. Here we took the example service namely SET(Secure Electronic Transaction) and in this case study we have discussed some security techniques to avoid this manipulation of the credential data which would guarantee an increased customer base and eventually prove to be very profitable.