Abstract FPSOs have a risk profile different from fixed platforms and commercial trading tankers. Being stationed in one location and routinely visited by supply boats and shuttle tankers. FPSOs can be collided by these ships. In addition, passing ships also pose a collision risk if an FPSO is close to a sailing route. This paper presents a systematic approach to address the risk of collision and contact damage. It is aimed to propose a framework that can be applied in structural designs and risk assessment schemes. The focus is placed on accident scenarios, evaluation approaches and acceptance criteria, the three major issues for a risk assessment and also for a relevant design standard. Accident scenarios and the associated occurrence frequency may be determined through statistics from historical data, expert opinions, and risk analysis, depending on different situations. A spectrum of tools has been developed in recent years that predicts the structural damage of collisions, including simple formulae, simplified analytical methods, simplified FEM, and non-linear FEM simulations. Those based on the advanced structural crashworthiness theory provide powerful and practical tools, and are well suited for design evaluations and risk analysis. Contact damage is more likely to occur than accidents resulting in rupture of shell plating. However, this type of accident has received very limited attention. An analytical approach is presented for analyzing contact damage that can be used during earlier design stage. Acceptance criteria for collision and contact accidents are discussed. The emphasis is on structural integrity including local strength and hull performance. Introduction FPSOs have a risk profile different from fixed platforms and commercial trading tankers. Being stationed in one location and routinely visited by supply boats and shuttle tankers. FPSOs can be collided by these ships. In addition, passing ships also pose a collision risk if an FPSO is close to a sailing route. A collision accident can lead to costly consequences in loss of lives, damage to property and/or environment. As past accidents have demonstrated, the indirect cost of compensation and bad publicity can be even higher. This has been the driving force in recent years for developing standards for design against collision accidents for trading oil tankers. A collision with low kinetic energy can result in permanent deformations of side structures instead of rupture of side shell. This low-energy collision is sometimes called "contact accident". Usually, contact damage is not catastrophic and does not pose a threat to the safety of the installation and the protection of environment. Contact damage receives little attention. This paper presents a systematic approach to address the risk of collision and contact damage. It proposes a framework that can be applied in structural design and risk assessment. Discussion is given to accident scenarios and acceptance criteria.