This session examines tight hydrocarbon reservoirs, which are widely distributed across the world and contain significant volumes of oil and gas locked within low-permeability formations. To unlock and produce these resources, a multidisciplinary approach to evaluating tight reservoirs is required. Tight hydrocarbon systems feature very low matrix permeability (< 1–5 mD) and low porosity (< 10–15%). Natural fluids cannot easily flow through the rock matrix, and characterisation therefore focuses on mapping complex micro-pore structures, natural fractures, and "sweet spots" to design optimal techniques such as drilling horizontal wells and/or applying specialised hydraulic and acid fracturing methods to reach and produce the oil and gas as much as can from those tight reservoirs.