Abstract: The invention describes a novel method for securing the Business Logic of on-line Internet applications against application manipulation attacks by means of identifying the exact manner in which the application was intended to be used (Intended Use Guidelines) and enforcing said intended use by embedding unique identification keys inside outgoing HTTP (HyperText Transfer Protocol) response headers and/or HTTP response HTML (HyperText Markup Language) streams and validating subsequent HTTP requests before submitting an independent HTTP request to a standard Web Server (HTTP daemon). Each unique identification key is mapped to one or more Intended Use Guidelines. The software is designed to be positioned behind an Internet-facing network firewall and in front of a standard Web Server.