Timely access to quality data is essential for the understanding of marine processes. The International Oceanographic Data and Information Exchange (IODE) programme of IOC UNESCO, through its distributed network of National Oceanographic Data Centres (NODCs), is establishing the Ocean Data Portal (ODP) to facilitate seamless access to marine data/services and to promote the exchange and dissemination of marine data and services. Conceptually, ODP is aimed to implement the “end to end” data management and “one-stop shop” approach. ODP can support the full range of processes including data discovery, evaluation (through visualization and metadata review) and access and delivers a standards-based infrastructure that provides integration of marine data and services across the NODC network. In fact the ODP technology is not dependent on specific thematic (discipline) content and can be scaled to other communities. The key principle behind the ODP is its interoperability with existing systems and the IODE is working closely with the Joint WMO-IOC Technical Commission for Oceanography and Marine Meteorology (JCOMM) to ensure the ODP is interoperable with the WMO Information System (WIS) that will provide access to marine meteorological and oceanographic data and information to serve a number of applications, including climate. Following the IODE recommendations high priority has been assigned also to the interaction with the SeaDataNet (SDN) and Global Earth Observation System of System (GEOSS). The ODP development is carried out under leadership of the joint IODE/JCOMM Expert Group for Data Management Practices (ETDMP) and on basis of technologies of Unified state system of information on the oceans of the Russian Federation. The implementation had two stages: Version 1 and 2. The ODP v1 operated from 2009 and currently its distributed data source network includes more 10 data providers in IODE data centres from the BackSea region, Canada, Australia, UK, the East Asian and South America region. ODP v2 has improved capabilities based on use of new information technologies and international interoperability standards and tools. At this time the ODP v.2 is in a pre-operational phase.