Systems Practice in Engineering (SPiE): A Developing Research Agenda outlines the context and challenges for systems engineering research. It discusses the need to [1] improve the academic profile and standing of systems engineering, [2] address the complexity of real-world problems through an interdisciplinary approach combining engineering and social sciences, and [3] develop a coherent research agenda through industry-academic collaboration. The document explores tensions between traditional academic research and high-impact, application-driven systems research and argues for establishing an intellectually rigorous foundation to advance the field.