Neuroendocrinology deals with the integrated functioning of the nervous and endocrine systems in maintaining homeostasis and coordinating adaptive responses. This chapter outlines the fundamental concepts of neuroendocrine regulation, emphasizing the pivotal role of the hypothalamus in linking neural signals with hormonal secretion. Major hypothalamic–pituitary axes, including the adrenal, gonadal, thyroid, and growth hormone axes, are described to illustrate systemic control of stress, metabolism, reproduction, and growth. Interactions at the cellular level involving neurotransmitters, hormones, shared receptors, and intracellular signaling pathways are discussed along with feedback mechanisms that ensure physiological stability. The chapter also highlights integration with the immune and autonomic nervous systems and briefly reviews the clinical implications of neuroendocrine dysregulation.