According to the Department of Homeland Security, 90% of security incidents result from exploits against defects in the design or code of software. This is even so in 2002 Bill Gates already requested a paradigm shift from features to security in his trustworthy computing memo with the sentence "So now, when we face a choice between adding features and resolving security issues, we need to choose security." Lucas v. Stockhausen will show in his talk how applications can be built in a secure way using existing technologies and how developers can be best involved into this.