My favourite case study I use in teaching CI courses, particularly in my introductory or managerial ones, is Competitive Intelligence Policy at Pratt & Whitney, HBS case 9-394-154. This one was done some 15+ years ago, but deals with the real-world establishment of ethics policy at the company, including dealing with the challenges created in trying to implement the policy and the key differences in its application between two very different SBUs/divisions. It also provides a number of short follow-on ethical dilemmas that always generate excellent discussion. This case is uniquely useful in helping students understand real-world CI ethics and management issues!