Problem statement: The present paper suggests that despite several decades of design research, most of the models presented for the design process have a partialist approach and have not been able to provide a holistic definition of it. In addition to reducing the overall process, this situation has hindered its comprehensive understanding. Research objective: This study seeks to provide a comprehensive description of the design process based on a systemic approach (as one of the holistic approaches). Research method: For this objective, both theoretical and experimental methods have been used to examine the systemic features of the process. The interaction of the process with the environment, identification of its components, and the ability to be controlled through feedbacks have been achieved theoretically and with the help of logical reasoning and inference from the opinions of experts. In the experimental section, to study the relationships (component/ total), totality, and structure, it has been referred to the design process of industrial subjects (in a power plant). In this section, the techniques of “ open structured interview” , “ preparation of design protocols, ” and “ documentation of design products” have been used to collect primary data, and quantitative/ qualitative content analysis has been used to evaluate the data. The research participants include ten experts in the design of power plant complexes. Conclusion: The results confirm that the design process, as an open system, has a flexible structure and is controlled by feedbacks. Their action, knowledge, manner, agent, and tool, together with their sub-components, are in the form of components and interact with the whole process.