Process plant start-up is a key element in the transition from the project phase to business operation. A proper start-up phase ensures safe and reliable process plant operations. When project start-up tasks are not properly considered, they can become activities performed at the end of a project with no clear acknowledgement of ownership. Failure to take start-up considerations into account in all project phases can have serious negative effects on net present value for a prolonged period of time over the total asset life cycle. To ensure project success, the start-up phase must be supported by those participating in both the project and business teams, and this starts with confirmation by top management that plant start-up is a fully-fledged project phase. This study presents the challenges that are most common within the process industry and can be solved or mitigated with adding proper actions and implementations into project management and execution processes. Providing a valuable contribution to the knowledge around start-up of new process plants, the study is based on experience based empirical observations and a comprehensive literature review.