This paper provides a pragmatic and objective diagnostic approach to the assessment of public investment management systems for governments. Since weaknesses in public investment management can negate the core argument that additional fiscal space allocated to public investments could enhance future economic prospects, attention to the processes that govern public investment selection and management is critical. The paper begins with a description of eight key "must-have" features of a well-functioning public investment system: (1) investment guidance, project development, and preliminary screening; (2) formal project appraisal; (3) independent review of appraisal; (4) project selection and budgeting; (5) project implementation; (6) project adjustment; (7) facility operation; and (8) project evaluation. The emphasis is placed on the basic processes and controls (linked at appropriate stages to broader budget processes) that are likely to yield the greatest assurance of efficiency in public investment decisions. The approach does not seek to identify best practice, but rather to identify the "must have" institutional features that would address major risks and provide an effective systemic process for managing public investments. The authors also develop a diagnostic framework to assess the main stages of the public investment management cycle. In principle, the identification of core weaknesses will allow reforms to focus scarce managerial and technical resources where they will yield the greatest impact. In addition, the framework is intended to motivate governments to undertake periodic self-assessments of their public investment systems and design reforms to enhance the productivity of public investment.