This chapter provides an overview of key issues for the world ocean in globalisation. It is prompted by recent scientific findings suggesting that the Earth may be undergoing a shift from the latest known geological epoch, the Holocene, to a new one marked by the human impact - the Anthropocene, meaning that the Earth System may be leaving its stable period and facing new, uncertain prospects. This hypothesis of the Anthropocene, it is argued, should invite fundamental reflection on our current social structures, in which the relationship with the status and uses of the oceans plays a fundamental role. The oceans today are, however, impacted by many different factors that interact synergistically. As a result, the effects on marine ecosystems are continuously accelerating. A brief overview of several key issue-areas is provided: CO2, climate change and the oceans; sources and effects of marine pollution; transfer and introduction of invasive alien species; habitat destruction; poorly managed fisheries; offshore oil and gas activity; shipping and maritime transport; marine protected areas; and regional responses to global challenges in the seas surrounding Europe. Against this backdrop, it is argued that various aspects of globalisation, affecting also the use of the seas, have probably had more impact on the state of the marine environ¬ment and resources in the past several decades than all human activities have had in the entire span of prior human history. It is concluded that that our individual and common goal must be to channel scientific and technological capabilities, and policy objec¬tives and legal rules, so as to make it possible to reconcile human impacts on the Earth System with the absorbing capacity of the planet and its component elements, which we often like to call ‘resources’.