With the proliferation of many innovative data communications services such as social networks, cloud computing, location-based service, and Internet of Things, security and privacy issues become more and more demanding and challenging. In addition, wireless physical layer secrecy has attracted much attention in recent years due to the broadcast nature of the wireless medium and its inherent vulnerability to eavesdropping. While most workshops and symposiums on physical layer secrecy focus on the information-theoretic aspect, we look specifically at the signal processing aspects of secure physical layer communications. This workshop aims to bring together academics and industry professionals in the signal processing area as well to practitioners and engineers working on the security and privacy aspects of data communications and computer networks. This workshop will also provide a forum to present and discuss emerging ideas, progresses and trends in this highly challenging research field. We invite contributions that apply these signal processing approaches to more advanced wired and wireless systems, such as OFDM systems, cognitive radio, multi-hop networks etc. This will draw interest from researchers that wish to pursue the topic further in these new directions.