Abstract-In Cloud computing, the data are not only managed by the data owner but also by Cloud providers. Sophisticated Clouds collaboration scenarios require that these data objects can be accessed distributively among Cloud providers, while still being under the control of data owners. It brings security challenges for distributed authorization and trust management in which existing proposed schemes have not fully solved. In this paper, we propose a Dynamic Trust Establishment approach which can incorporate into Cloud provisioning life-cycles for the multi-provider Intercloud environment. It relies on attribute-based policies as the mechanism for trust evaluation and delegation. The paper also presents a practical implementation approach for attribute-based policies using Multi-type Interval Decision Diagrams which has advantage in term of evaluation complexity.