Is the hypothalamus part of the limbic system? I believe the hypothalamus is involved in control of appetite and defensive and reproductive behaviours, which are functions of the limbic system, and according to this website http://webspace.ship.edu/cgboer/limbicsystem.html it would seem that it is part of the limbic system, however Wikipedia and other sites seem to disagree... Any help would be much appreciated :)
Short answer
Yes

Background
There is no universal agreement on the total list of structures comprising the limbic system. The brain regions constituting the limbic system according to Rajmohan &amp; Mohandas (2007) are:


Limbic cortex
Cingulate gyrus
Parahippocampal gyrus
Hippocampal formation
The dentate gyrus
Hippocampus
Subicular Complex
Amygdala
Septal area
Hypothalamus


Note that wikipedia agrees on the inclusion of the hypothalamus. I dare say that in general the hypothalamus is included as an essential component of the limbic system, as it is involved in the expression of emotional responses, such as rage and fear (Purves et al, 2001).

References
- Purves et al, Neuroscience, 2nd ed. Sunderland (MA): Sinauer Associates; 2001
- Rajmohan &amp; Mohandas Indian J Psychiatry (2007); 49(2): 132–9)