AccordingtoFrancoisBancillonandWonKim[SIGMODRECORD,Vol.19,No. 4, December 1990], object-oriented databases started in around 1983. Twen- seven years later this publication contains the proceedings of the Third Inter- tional Conference on Object-Oriented Databases (ICOODB 2010). Two questions arise from this - why only the third, and what is of interest in the ?eld of object-oriented databases in 2010? The ?rst question is easy - in the 1980s and 1990s there were a number of conferences supporting the c- munity - the International Workshops on Persistent Object Systems started by Malcolm Atkinson and Ron Morrison, the EDBT series, and the International Workshop on Database Programming Languages. These database-oriented c- ferences complimented other OO conferences including OOPSLA and ECOOP, but towards the end of the last century they dwindled in popularity and ev- tually died out. In 2008 the First International Conference on Object Databases was held in Berlin. In 2009 the second ICOODB conference was held at the ETH in Zurich as a scienti?c peer-reviewed conference. What is particular about ICOODB is that the conference series was est- lished to address the needs of both industry and researcherswho had an interest in object databases, in innovative ways to bring objects and databases together and in alternatives/extensions to relational databases. The ?rst conference set the mould for those to follow - a combination of theory and practice with one day focusing on the theory of object databases and the second focusing on their practical use and implementation.

Keynotes.- Search Computing Challenges and Directions.- Searching the Web of Objects.- Unifying Remote Data, Remote Procedures, and Web Services.- Keynote Panel "New and Old Data Stores".- Regular Papers.- Revisiting Schema Evolution in Object Databases in Support of Agile Development.- The Case for Object Databases in Cloud Data Management.- Query Optimization by Result Caching in the Stack-Based Approach.- A Flexible Object Model and Algebra for Uniform Access to Object Databases.- Data Model Driven Implementation of Web Cooperation Systems with Tricia.- iBLOB: Complex Object Management in Databases through Intelligent Binary Large Objects.- Object-Oriented Constraints for XML Schema.- Solving ORM by MAGIC:MApping GeneratIon and Composition.- Closing Schemas in Object-Relational Databases.- A Comparative Study of the Features and Performance of ORM Tools in a .NET Environment.