Agile methodologies have become increasingly popular for enhancing quality and customer satisfaction, shortening delivery times, decreasing risk in changing environments, and improving team morale and productivity for a wide variety of complex systems. However, there is limited research regarding how agile attributes and principles can help achieve high European Cooperation for Space Standardization (ECSS) compliance levels, resulting in increased Technology Readiness Levels (TRL) and commercialization potential for the product. Accordingly, the objectives of this research are to identify and prioritize the level of significance of the critical attributes for the successful implementation of agile project management in the space industry and develop an agile framework for ECSS compliance. A multi-phase research methodology was adopted, including a systematic literature review to identify the main attributes of Agile ECSS compliance; surveys to assess the identified attributes; Analytical Hierarchy Process(AHP)-based model to quantify their level of significance; semistructured interviews with aerospace experts to develop an Agile framework for ECSS compliance; and Lego Serious Play with start-ups decision makers to validate the developed framework. Based on the adopted methodology, the authors identified a total of 43 Agile attributes grouped under seven categories, namely organizational-related, management-related, project-related, process-related, technical-related, team-related, and customer-related attributes. Depending on the AHP analysis of the identified attributes, a five-level agile ECSS compliance framework was developed. Level 1 includes leadership vision and mission attributes. Level 2 includes team commitment and top management support attributes. Level 3 includes joint understanding of uncertainty attribute. Furthermore, level 4 includes technical training and learning, manufacturing system flexibility and customer involvement attributes. Finally, Level 5 includes ECSS compliance and its linkage to the TRL of the product and the process of product commercialization. The results of this study have several implications for researchers and practitioners. First, it provides an in-depth understanding of the AHP method for determining the priorities for the identified agile attributes, which could aid researchers and practitioners working in other space hardware and software engineering domains to implement the AHP method. Second, the 43 identified agile attributes provide a knowledge base classification/taxonomy for practitioners to assist in scaling agile development. Third, the developed compliance framework clarifies the interdependencies among the critical agile attributes, which can assist in identifying the required capabilities necessary to achieve business excellence.