The advancements in the Information and Communication Technologies (ICTs) have introduced new computing paradigms (e.g., cloud computing, pervasive and ubiquitous computing, ambient intelligence and aware-computing) where the techniques for processing, storing, communicating, sharing, and disseminating information have radically changed. These novel computing paradigms bring enormous benefits: the availability of a universal access to data; the reduction in power, storage, hardware, and software costs; and the availability of elastic storage and computation services. While these advantages are appealing, as a side effect there is a tremendous risk of exposure of confidential or sensitive information to privacy breaches. WPES is a yearly forum, this year at its 15th edition, aiming at discussing the open privacy challenges, emerging directions, and original novel approaches for guaranteeing privacy in today's global interconnected society.