How to use group dynamics to make the right decisions? Organizations evolve in a context of change, uncertainty, and complexity. Employees need to understand what is at stake and to participate in decisions. However, if managers and leaders need to mobilize collective intelligence to succeed, they have little or no training in working in large groups. Collaborative design is a development process involving stakeholders. Workshops, led by facilitators from within the company or from external firms, take place during seminars lasting one or more days. In a complex situation such as a merger, the reframing of a project, a business choice, the launch of a product, the development of an organization, or the implementation of a strategy, they bring together from fifteen to more than one hundred and fifty participants around an objective: to analyze the situation, to find out how to deal with and solve a problem, to produce shared representations or decisions, and to commit to action. This book is based on the author's proven practices. It will help executives and managers co-design and co-facilitate these workshops so that they produce tangible results. Very concrete, it is illustrated with various cases such as a large aeronautical company, a research laboratory, an industrial SME, a professional group, a cooperative, or a school. After an introduction on collaborative design, it is organized into four parts: 1. Understanding, imagining, and giving meaning 2. Planning, projecting, and giving substance 3. Expanding, improvising, and giving rhythm 4. Planting, growing, and sustaining life Each of the twenty-seven practical sections can be approached independently thanks to a common plan: issues, keys, and examples. The book is prefaced by Gabrielle Rolland, consultant in change management, speaker and writer on leadership and collective intelligence, and author of "Seniors, votre avenir a un futur" (Laffont, 2009).