Collecting quantitative and extensive datasets in the field is fundamental in structural geology, stratigraphy, and sedimentology, rock mechanics, and in other fields of the Earth and planetary sciences. Digital Outcrop Models (DOMs) provide a 3D framework for collecting these large datasets and can be obtained from laser scanning or photogrammetric surveys, carried out either with an avionic platform (airplane, helicopter, drone) or with terrestrial methods. In this chapter we review best-practice methods for collecting DOMs, focusing particularly on terrestrial and drone photogrammetric surveys and on critical issues that determine their efficiency, reliability, and accuracy. Then we compare the two main formats for DOMs: point clouds (PC-DOMs) and textured surfaces (TS-DOMs). Finally, we outline typical goals and workflows for the geological interpretation of DOMs on PC- and TS-DOMs, either from laser scanning or photogrammetric surveys.