This unit portfolio for Week 1 of PPMP20012 explores the relevance of systems thinking to project management and how it can aid project managers in solving project problems. It covers different systems thinking tools and techniques, assesses the relevance of systems engineering to project cases, and discusses the importance of appropriate selection of project management application systems. The portfolio also proposes appropriate project, program, and portfolio application systems to support successful project execution in different industry domains. Readings and supporting documentation are included.