Structural systems are under deterioration due to ageing, mechanical stressors, and harsh environment, among other threats. Corrosion and fatigue can cause gradual structural deterioration. Moreover, natural and man-made hazards may lead to a sudden drop in the structural performance. Inspection and maintenance actions are performed to monitor the structural safety and maintain the performance over certain thresholds. However, these actions must be effectively planned throughout the life-cycle of a system to ensure the optimum budget allocation and maximum possible service life without adverse effects on the structural system safety. Life-cycle engineering provides rational means to optimise life-cycle aspects, starting from the initial design and construction to dismantling and replacing the system at the end of its service life. This paper presents a brief overview of the recent research achievements in the field of life-cycle engineering for civil and marine structural systems and indicates future directions in this research field. Several aspects of life-cycle engineering are presented, including the performance prediction under uncertainty and optimisation of life-cycle cost and intervention activities, as well as the role of structural health monitoring and non-destructive testing techniques in supporting the life-cycle management decisions. Risk, resilience, sustainability, and their integration into the life-cycle management are also discussed.