Despite the significant research efforts devoted to the microgrid and smart grid areas, numerous problems related to real world implementations still remain unsolved. The present special issue was announced with the objective of addressing and disseminating state-of-the-art R&D results on microgrids to bring together researchers from both academia and industry with the goal of fostering interactions among stakeholders. In response, 190 two-page extended abstracts were received and considered for the first round of reviews. Authors of about 60 selected abstracts were then invited to submit the full papers in the second round and out of them 27 high-quality manuscripts were ultimately approved and included in this special issue. These papers are organized according to the following four topics: 1) Microgrid dynamic performance, control/operational strategies, and voltage/frequency regulation. Here, 14 papers deal with the dynamic modeling and performance ofmicrogrid or its building blocks and propose appropriate control/operational strategies or voltage/frequency regulation approaches. 2) Reliability and power quality aspects of microgrids, where seven papers about the microgrid reliability assessment techniques, impact of distributed energy resources on microgrid reliability indices, and the microgrid power quality analysis are presented. 3) Fault modeling and protection schemes. This section consists of four papers focusing on series fault modeling in dc microgrids, overvoltage protection of photovoltaic generators, and protection schemes tailored for the microgrid operational characteristics. 4) Others: Two practical papers about the impact of microgrids on the planning of the medium-voltage distribution networks and characterization of the Vanadium Redox battery are presented.