The Microwave Integrated Retrieval System (MiRS) is the official NOAA operational microwave-only retrieval system. It was first introduced into operations in 2007 and currently processes data from NOAA-18, -19, MetopA, MetopB, DMSP F-17, F-18, GPM, Megha-Tropiques, Suomi-NPP, and the recently-launched NOAA-20 satellite. The retrieval algorithm is based on a 1-dimensional variational approach in which the fundamental physical attributes affecting the microwave observations are retrieved physically, including the profile of temperature, water vapor, hydrometeors, as well as surface emissivity and temperature. Further post-processing of the core retrieved variables allows for production of derived products such as surface precipitation rate, sea ice concentration and age, and snow water equivalent. Due to its use of microwave data only, MiRS has the capability of operating in "all weather" conditions. Additionally, the processing of data from multiple polar orbiting satellite platforms leads to higher effective temporal and spatial coverage that increases with latitude. The presentation will cover the background of the MiRS retrieval approach, and then move on to discussion of retrieval products, user applications, and recent work aimed at scientific improvements. Where possible, examples will be chosen that are relevant to users in high-latitude regions such as Alaska.