This article presents a conceptual and theory-creating framework for Persuasive Systems Design (PSD), which aims to provide a systematic approach for developing and evaluating persuasive software solutions. The authors define seven postulates that should be considered when designing or evaluating persuasive systems, including how users are viewed, persuasion strategies, and system features. They also discuss the process of designing and evaluating persuasive systems, describing what kind of content and software functionality may be found in the final product. The article outlines 28 design principles for persuasive system content and functionality, describing example software requirements and implementations. Some of the design principles are novel, and a new categorization of these principles is proposed, consisting of the primary task, dialogue, system credibility, and social support categories. Persuasive systems are defined as computerized software or information systems designed to reinforce, change, or shape attitudes or behaviors without using coercion or deception. The article discusses the process of designing and evaluating persuasive systems, highlighting the importance of understanding the persuasion context, including the intent, event, and strategy. It also describes how persuasive systems may utilize either computer-human persuasion or computer-mediated persuasion. The article emphasizes the importance of analyzing the persuasion context, which involves understanding the roles of the persuader, persuadee, message, channel, and the larger context. It also discusses the use of cognitive consistency theory and the theory of reasoned action in understanding persuasion. The article further outlines the design principles for persuasive systems, including the primary task, dialogue, system credibility, and social support categories. It provides an example of how the framework can be applied to a real-world system, such as the Nike+ running system, which incorporates several distinct persuasive techniques in its functionality. The article concludes by emphasizing the importance of the proposed framework in motivating and persuading users to reach their personal goals. It also highlights the practical implications of the framework and the need for future research to demonstrate its applicability in various real-life design and usage situations. The authors also acknowledge the contributions of the anonymous reviewers and provide a list of references.This article presents a conceptual and theory-creating framework for Persuasive Systems Design (PSD), which aims to provide a systematic approach for developing and evaluating persuasive software solutions. The authors define seven postulates that should be considered when designing or evaluating persuasive systems, including how users are viewed, persuasion strategies, and system features. They also discuss the process of designing and evaluating persuasive systems, describing what kind of content and software functionality may be found in the final product. The article outlines 28 design principles for persuasive system content and functionality, describing example software requirements and implementations. Some of the design principles are novel, and a new categorization of these principles is proposed, consisting of the primary task, dialogue, system credibility, and social support categories. Persuasive systems are defined as computerized software or information systems designed to reinforce, change, or shape attitudes or behaviors without using coercion or deception. The article discusses the process of designing and evaluating persuasive systems, highlighting the importance of understanding the persuasion context, including the intent, event, and strategy. It also describes how persuasive systems may utilize either computer-human persuasion or computer-mediated persuasion. The article emphasizes the importance of analyzing the persuasion context, which involves understanding the roles of the persuader, persuadee, message, channel, and the larger context. It also discusses the use of cognitive consistency theory and the theory of reasoned action in understanding persuasion. The article further outlines the design principles for persuasive systems, including the primary task, dialogue, system credibility, and social support categories. It provides an example of how the framework can be applied to a real-world system, such as the Nike+ running system, which incorporates several distinct persuasive techniques in its functionality. The article concludes by emphasizing the importance of the proposed framework in motivating and persuading users to reach their personal goals. It also highlights the practical implications of the framework and the need for future research to demonstrate its applicability in various real-life design and usage situations. The authors also acknowledge the contributions of the anonymous reviewers and provide a list of references.