The 4th PLMWS Workshop will take place during the 2017 IEEE CNS in Las Vegas, NV, USA, Oct 9-11, 2017. Previously unpublished contributions in wireless security based on physical-layer methods are solicited, including (but not limited to): Secrecy capacity of wireless channels Secure communication under adversarial attacks Practical code design for physical layer security Secure cross-layer design techniques Secure communication with an uncertain physical layer Jamming-assisted secure wireless transmission Cooperative secure communications Secret key generation and agreement PUF- and (wireless)-channel-based authentication Practical and implementation issues.