Cloud computing can be characterized as the culmination of the integration of computing and data infrastructures to provide a scalable, agile and cost-effective approach to support the ever-growing critical IT needs of both enterprises and the general public. Massive data centers providing storage and processing power with fast network connectivity form the core of the support infrastructure for the cloud. It is thus imperative that we get the cloud and consequently the underlying data center infrastructure right so that both the deployment, operation and maintenance of the infrastructure is efficient, cost-effective and meets the performance, dependability and security requirements. The Third International Workshop on Dependability of Clouds, Data Centers and Virtual Machine Technology (DCDV 2013) will bring together academics and industry practitioners in order to share experiences, discuss existing state-of-the-art and set directions for future research and evolution for this dynamic and rapidly evolving field.