The seminar by Clincy Cleetus highlights the decision-making process in organizations, which involves setting goals, exploring alternatives, and implementing solutions. It outlines different types of decisions, categorized by purpose (strategic, management control, operational) and programmability (programmed, non-programmed, semi-structured). The importance of Decision Support Systems (DSS) is emphasized, describing their role in aiding decision-making through interactive data processing, the use of various decision models, and the facilitation of managerial functions.