An in-depth case study is used to illustrate the transition senior consultants can make from the role of executive coach to a role conceptualized by the author as trusted leadership advisor (TLA) in long-term engagements with senior business executives. In this engagement, spanning several years, the client ultimately became CEO of a global entity. Factors addressed in the case include the client’s development issues, his progress, and the challenge of his simultaneously making developmental progress while managing a difficult boss and understanding how the company culture in some ways exacerbated his leadership issues. A number of key practice factors are specified as potential guidance for practitioners already working or aspiring to work with CEOs and other senior business leaders. These factors, embedded in the application of an integrated practice model, include how the TLA guided and conceptualized the engagement, useful tools including written summaries and constructive triangulation, and the management of multiple roles.