It's true! The hypothalamus really is a great link between the nervous and endocrine systems. While the endocrinologists would smack me for oversimplifying this, here goes nothing! The hypothalamus is kinda the "master regulator" of the body's systems. It takes input from all different sections of the brain and "makes decisions" on what the body needs to do. Often this involves remote systems of the body, such as the skin or the reproductive tracts. In order to send signals such a long distance to such a wide variety of organs, the hypothalamus taps into the endocrine system. Generally speaking, the hypothalamus talks to the endocrine system by way of the Pituitary Gland. The pituitary gland can be divided into two parts. (Perhaps each part of the gland and it's interface with the hypothalamus can be your two answers here). Real quick description of the pituitary: it's a small pea-sized organ hanging below your optic nerves in the brain. It secretes a TON of regulatory hormones that pretty much control the entire endocrine system. It's the "master gland" of the endocrine system, and it takes its orders from the hypothalamus. Anyways. The first part of the pituitary we'll discuss is the posterior pituitary. It is actually a direct extension of the hypothalamus, in fact, the two are one in the same. Neurons from the hypothalamus send their axons down into the posterior pituitary where they release their neurotransmitters (which are hormones!) into the general circulation. Thus, there's a direct neural-endocrine interface here. Nerves from the hypothalamus release endocrine hormones! The hormones released here (there's two of them) control things such as water regulation in the kidney and uterine contractions in those people so equipped. The other half of the pituitary, the anterior pituitary, has a wide range of functions. It two takes its orders from the hypothalamus, but it does so in a rather different way. There's a special set of blood vessels connecting the hypothalamus and the pituitary. When the hypothalamus wants to signal the anterior pituitary to do something, it releases a specific neurotransmitter into these blood vessels, where they travel to the pituitary and are picked up by cells. In response, these cells release their own special hormones into the general circulation, which travel to the various organs in the body and control endocrine function. There's many roles of the hormones here, including growth, sexual development, metabolism, and quite a few others as well. So to summarize: the two ways the hypothalamus interfaces the nervous system and the endocrine system: 1) Direct neural release of endocrine hormones in the posterior pituitary. 2)Chemical signalling of the anterior pituitary to release hormones. Hope that helps!! --SP