This special issue on Unmanned Aerial Systems (UAS) for Environmental Applications makes three important contributions:
(1) It marked the launch of the new Drones section in the International Journal of Remote Sensing.
(2) It captures key contributions from the 5th Small Unmanned Aerial Systems (sUAS) for Environmental Research (UAS4Enviro2017) conference, which was held at the University of Trás-os-Montes e Alto Douro, Portugal, from 28 to 30 of June 2017.
(3) In addition to the papers presented at the conference, the special issue collects a wide range of papers on UAS remote sensing. In total, the special issue comprises 36 papers from 14 countries in Africa, Asia, Europe, North America and South America. The topics range from methodological innovations to applications, with a special focus on natural vegetation, agriculture, geomorphology and animal surveys.