Producing oil and gas from shale formations was enabled by continuous advancements in technology that unlocked the complexity of unconventional reservoirs. Today's crucial challenge is to learn how to characterize these resources with a well-integrated geoscience and engineering evaluation. This book aims to provide practical and actionable steps to enable readers to evaluate any unconventional reservoir from core to field scale and assess primary and enhanced oil recovery (EOR). The evaluation begins by characterizing the petroleum system to determine the target formations. Laboratory experiments are made to investigate key properties of produced and potential EOR fluids and interactions with host rocks. Nano-scale rock properties are examined to quantify the deliverability of the matrix-fracture system. Well-level flow characterization is achieved by analyzing short duration well tests and long-term well production history. All reservoir properties culminate into a compositional dual-porosity reservoir model to simulate production performance and EOR strategies. These steps are applied to one of the largest, liquid rich shale plays in North America, the Bakken reservoir.