This chapter provides a comprehensive overview of neutron detection and dosimetry. It details various neutron interaction mechanisms, including elastic and inelastic scattering, radiative capture, charged particle reactions, and fission, and explains how these processes lead to energy transfer and deposition in materials, particularly human tissue and detector media. The chapter discusses key dosimetric concepts, such as relative biological effectiveness (RBE) and radiation weighting factors, and explores the energy dependence of neutron cross-sections. A significant portion is dedicated to the theory and practical aspects of different neutron detector types, categorizing them into active detectors (like scintillators, ionization chambers, and proportional counters, including moderated versions) and passive detectors (such as activation foils, nuclear emulsions, etched track detectors, TLDs/OSLDs, and bubble detectors). The chapter also examines diverse applications of neutron dosimetry in fields like radiation protection, shielding evaluation, particle therapy (addressing secondary neutron production), fast neutron therapy, Boron Neutron Capture Therapy (BNCT), and microdosimetry. Finally, it addresses the inherent limitations and challenges associated with neutron detection and measurement.