The next generation mobile network, the 5G, is expected to unlock many new services and provide a platform to enable growth in many industries from smart cities, public safety, independent living, health, manufacturing, energy, agriculture, to entertainment and education. One of the key requirements for 5G is to provide ubiquitous connections to billions devices and with multi-Gbps data transmission to meet 1,000 times increased capacity. To bring 5G to reality, there are countless challenges lying ahead, ranging from spectral regulation to system architecture through to network management. Many of the most difficult scientific and mathematical challenges that need to be overcome to realise 5G are located at the “Physical Layer”, due to some fundamental limitations imposed by the nature of electromagnetic energy used. As a result, significant research is required to enable advanced microelectronic circuits and smart algorithms needed to achieve a working system in hardware. The IMWS-5G 2018 workshop provides a unique opportunity to bring together researchers and practitioners of different background to share the most recent advances in hardware and system technologies for 5G wireless communications. The workshop is sponsored by the IEEE Microwave Theory and Techniques Society (MTT-S), IEEE 5G Initiative and the European Microwave Association (EuMA). It will be held at University College Dublin, Ireland. The conference will feature an exciting technical program, an industry exhibit, and invited talks by worldwide recognized experts in 5G.