For study purposes, an ocean industry was defined to be one that can be reached via a fresh or salt water path. This includes industries with both full and partial circumferential water perimeters. The type of threat assumed in the study had the following characteristics: highly credible in terms of previous experience, focused on and relevant to an attack on ocean assets, and a serious threat beyond the realm of simple industrial security. These criteria most closely fit a terrorist-type attack. The study first cataloged ocean assets of interest and then selected industries to be used in the evaluation of vulnerability to attack, followed by an assessment of the economic loss that could result from a successful attack. Descriptive material was acquired from the owners/operators to support the vulnerability and economic loss assessment analyses. Threat characterization was developed by establishing human and equipment variables of threat groups and assigning performance levels and hardware capability to each variable. Based on the vulnerabilities and potential economic losses, an assessment was made of the need for OIP. OIP recommendations were developed during the step-by-step progression of the study. The study concludes that U.S. ocean industries would be vulnerable to a terrorist attack with modest capabilities in the 1985 time frame. The destruction and results from the attack would probably shut down the facility. Damage inflicted by a terrorist attack would be dramatic, but not necessarily more severe than the damage wrought by a serious accident or natural catastrophe. Security recommendations are in the areas of policy, organization, and hardware. Tabular and graphic data are provided.