Somatostatin was originally characterised as a hypothalamic neurohormone responsible for the inhibition of pituitary Growth Hormone secretion. In mammals two genes encode for somatostatin-related peptides, somatostatin 14 and 28, and cortistatins, respectively. All peptides bind with similar affinities to the five cloned somatostatin receptors (sst), which belong to the GPCR family. Despite numerous studies, no clear behavioural function has yet been attributed to somatostatin-related peptides. This is due to the lack of good pharmacological tools (selective antagonists) and animal models. This review will focus on the recent development of such tools.