Micromorphology and submicromorphology—the microscopic study of soils in undisturbed thin sections and via scanning electron microscopy (SEM)—have become among the most powerful diagnostic tools in paleopedology and geoarchaeology. This chapter provides a comprehensive overview of (sub)micromorphological methods as applied to paleosols and related sediments. It highlights how micromorphological investigations allow for the identification of diagnostic features formed by pedogenesis, sedimentation, diagenesis, and anthropogenic activity, even in highly altered or polygenetic profiles. Particular attention is given to the challenges of distinguishing between pedogenic and lithogenic features and to the interpretation of complex multistage soil development and postburial transformations. Key sampling and preparation techniques for obtaining representative thin sections are discussed, emphasizing the importance of minimal disturbance and accurate contextual documentation. The chapter presents a systematic approach to the identification, description, and classification of micromorphological features, building on international standards and terminology. A broad spectrum of micromorphological proxies is described, including clay and silt coatings, secondary carbonate and gypsum microforms, organic and anthropogenic features, Fe-Mn pedofeatures, microstructure of the soil fabric, and more. The chapter further explores the value of micromorphology for reconstructing paleoenvironmental conditions, such as climate and landscape evolution, and for distinguishing developmental stages and processes in both buried and surface soils. Applications in archaeological contexts are also addressed, illustrating the role of soil micromorphology in understanding site formation, past land use, and the interplay between natural and cultural processes. Emerging trends are discussed, including the integration of digital image analysis, microtomography, and future prospects for quantitative micropaleopedology. Through detailed case studies and methodological recommendations, this chapter aims to serve as a reference for researchers and students applying micromorphological methods to soils and sediments in (pre)Quaternary and archaeological science and is also relevant to studies of modern soils.