Enterprise environmental factors (EEF) and organisational process assets (OPAs) are important inputs for most of the processes in all project management knowledge areas. This study assesses the effect of three important EEF and OPA input factors, project organisational support, project control and contingency planning, and project management processes, on project baseline and planning management. In addition, this study also investigates how much of an influence that effective project baseline and planning management has on company performance. Data were collected from 93 certified project management professionals (PMPs) registered with the Project Management Institute (PMI) in China. Our findings showed that firms that develop company-wide organisational support systems and company-wide procedures and processes for managing projects within an operations organisation do better in their overall performance.