A single economic agent controls a variety of activities. Each activity is associated with a privately observed piece of information. The information is relevant to the actions he will take in this activity, and to the vulnerability of this activity to attack by another agent. Actions should be chosen so as partially to hide the private information, as well as to be efficient in the productive sense. This paper gives a characterization of the optimal association of actions to activities based on the private information available. Some applications are discussed
