Trust Domains are an emergent concept for the design, deployment and assessment of collaborative IT systems. It acknowledges that trust is indispensable for collaborative human action and efficient cooperation. Domains of interactions enabled by trust can be found within organisations, between organisations, and between individuals spanning organisational borders, and they may evolve alongside or orthogonal to defined organisational processes and structures. A methodical approach for describing and designing collaborative information systems must therefore go beyond classical attributes of functional composition, reliability, and security. It must be complemented with aspects such as incentive structures, mutual expectations, reliance, and assurance. These are determinants for the level of trust between participating entities and trust in the underlying technical technical infrastructure. Co-located with CloudCom 2013, CTTD provides a forum for discussion between Trust Domain proponents and Cloud experts. It will therefore be a unique opportunity for exploring the application of Cloud technologies in the cutting-edge area of Trust Domains, as well as propagating Trust Domains concepts in secure Cloud systems.