The article discusses the structural components of design theories in Information Systems (IS), aiming to provide a systematic and usable formulation. It identifies eight components of design theories: (1) purpose and scope, (2) constructs, (3) principles of form and function, (4) artifact mutability, (5) testable propositions, (6) justificatory knowledge, (7) principles of implementation, and (8) an expository instantiation. These components address issues related to the specification of design theories for methodologies, interventions, and products. The paper builds on previous work by Walls et al. (1992) and extends it by incorporating additional components, such as constructs and artifact mutability, to provide a more complete definition of design theories. The paper also highlights the importance of design theories in providing a sound basis for arguments about the rigor and legitimacy of IS as an applied discipline. It emphasizes the need for a more formal and systematic approach to design theories, which can help in the cumulative building of knowledge rather than the re-invention of design artifacts. The paper concludes that design theories should be classified and compared based on their purpose and scope, and that a better theory should show an advance on all previous methods for solving the problem. The paper also discusses the importance of design theories in providing a framework for understanding and developing artifacts in IS.The article discusses the structural components of design theories in Information Systems (IS), aiming to provide a systematic and usable formulation. It identifies eight components of design theories: (1) purpose and scope, (2) constructs, (3) principles of form and function, (4) artifact mutability, (5) testable propositions, (6) justificatory knowledge, (7) principles of implementation, and (8) an expository instantiation. These components address issues related to the specification of design theories for methodologies, interventions, and products. The paper builds on previous work by Walls et al. (1992) and extends it by incorporating additional components, such as constructs and artifact mutability, to provide a more complete definition of design theories. The paper also highlights the importance of design theories in providing a sound basis for arguments about the rigor and legitimacy of IS as an applied discipline. It emphasizes the need for a more formal and systematic approach to design theories, which can help in the cumulative building of knowledge rather than the re-invention of design artifacts. The paper concludes that design theories should be classified and compared based on their purpose and scope, and that a better theory should show an advance on all previous methods for solving the problem. The paper also discusses the importance of design theories in providing a framework for understanding and developing artifacts in IS.