This systematic review examines the design principles and quality assurance practices that support effective blended practices in higher education. Conducted within the context of the EMBED+ project, the review synthesizes literature published between 2020 and 2025 to understand how blended practices can be designed, supported, and sustained across diverse organisational contexts. Across the literature, several design principles consistently emerge, including active learning and student engagement, meaningful assessment and feedback, scaffolding, learner autonomy, collaborative and social learning, curricular alignment, motivational and inclusive design, and real-world relevance supported by appropriate technology integration. At the organizational level, studies emphasize the role of sustained professional development, leadership commitment, coordinated support structures, and continuous cycles of evaluation and improvement. Collectively, this body of work indicates that technology is most effective when it is purposefully embedded to enhance interaction, flexibility, and personalized learning, rather than functioning as a driver of educational design in its own right. Quality assurance and maturity practices are less consistently addressed in the literature but remain critical for scalability and sustainability. Evidence suggests that institutions benefit from embedding quality processes throughout the lifecycle of blended education (planning, design, delivery, and evaluation) supported by frameworks, accessible data, and feedback mechanisms. Overall, the review provides a consolidated evidence base for strengthening blended practices in higher education. It shows that effective blended education is a whole-institution endeavor requiring continuous quality improvement. These findings inform the ongoing development of the EMBED+ project, including the renewed maturity model, the maturity matrix and its resources hub. It offers as well actionable insights for educators, researchers, and policymakers aiming to advance blended practices in higher education.