Photogrammetric applications of small Unmanned Aircraft Systems (sUAS) have been progressing rapidly in the last ten years and the mapping industry is under tremendous pressure to adopt the use of Unmanned Aircraft Systems in their mapping practices. This is fuelled mainly by affordability, ease of use, and the suitability of sUAS for small projects which makes it an attractive alternative to manned aircraft operations. Most of these drones carry sophisticated consumer grade cameras. The main objective of this chapter is to assess the accuracy of sUAS photogrammetry and its ability to satisfy mapping requirements. The chapter discusses sources of errors and their impact on the accuracy of the resulting geospatial products as well as discusses strengths and weaknesses of this technology with a case study as an example.