This chapter explores the neurobiological mechanisms of pleasure and reward in both humans and animals. It highlights the shared brain circuits that generate pleasure and reward, emphasizing the importance of understanding these mechanisms for treating affective disorders. The authors discuss the multiple psychological components of reward, including liking, wanting, and learning, and their corresponding neural substrates. They also delve into the role of specific brain regions such as the orbitofrontal cortex and the subcortical hedonic hotspots in generating pleasure. The chapter addresses the distinction between neural coding and causation of pleasure, and the challenges in distinguishing between these processes. Additionally, it examines the conscious and non-conscious aspects of pleasure, suggesting that pleasure can be divided into core 'liking' reactions and subjective liking experiences. The authors also discuss the integration of pleasure, motivation, and emotion in cognitive and systems neuroscience, and the potential role of the orbitofrontal cortex in mediating subjective hedonic experiences. Finally, they explore the possibility of cortical causation of pleasure and the implications for understanding and treating affective disorders.This chapter explores the neurobiological mechanisms of pleasure and reward in both humans and animals. It highlights the shared brain circuits that generate pleasure and reward, emphasizing the importance of understanding these mechanisms for treating affective disorders. The authors discuss the multiple psychological components of reward, including liking, wanting, and learning, and their corresponding neural substrates. They also delve into the role of specific brain regions such as the orbitofrontal cortex and the subcortical hedonic hotspots in generating pleasure. The chapter addresses the distinction between neural coding and causation of pleasure, and the challenges in distinguishing between these processes. Additionally, it examines the conscious and non-conscious aspects of pleasure, suggesting that pleasure can be divided into core 'liking' reactions and subjective liking experiences. The authors also discuss the integration of pleasure, motivation, and emotion in cognitive and systems neuroscience, and the potential role of the orbitofrontal cortex in mediating subjective hedonic experiences. Finally, they explore the possibility of cortical causation of pleasure and the implications for understanding and treating affective disorders.