With HCI, researchers conduct studies in interdisciplinary projects involving massive volume of data, artificial intelligence and machine learning capabilities. Awareness of the responsibility is emerging as a key concern for the HCI community. This Community will be impacted by the General Data Protection Regulation (GDPR) , that will enter into force on the 25th of May 2018. From that date, each data controller and data processor will face an increase of its legal obligations (in particular its accountability) under certain conditions. The GDPR encourages the adoption of Soft Law mechanisms, approved by the national competent authority on data protection, to demonstrate the compliance to the Regulation. Approved Guidelines, Codes of Conducts, Labeling, Marks and Seals dedicated to data protection, as well as certification mechanisms are some of the options proposed by the GDPR. There may be discrepancies between the realities of HCI fieldwork and the formal process of obtaining Soft Law approval by Competent Authorities dedicated to data protection. Given these issues, it is important for researchers to reflect on legal and ethical encounters in HCI research as a community. This workshop will provide a forum for researchers to share experiences about Soft Law they have put in place to increase Trust, Transparency and Accountability among the shareholders. These discussions will be used to develop a white paper of practical Soft Law mechanisms (certification, labeling, marks, seals…) emerging in HCI research with the aim to demonstrate that the GDPR may be an opportunity for the HCI community.