This invention concerns substituted diaza-spiro-[5.5]-undecane derivatives having neurokinin antagonistic activity, in particular NK.sub.1 antagonistic activity, a combined NK.sub.1/NK.sub.2 antagonistic activity, a combined NK.sub.1/NK.sub.3 antagonistic activity and a combined NK.sub.1/NK.sub.2/NK.sub.3 antagonistic activity, their preparation, compositions comprising them and their use as a medicine, in particular for the treatment and/or prophylaxis of schizophrenia, emesis, anxiety and depression, irritable bowel syndrome (IBS), circadian rhythm disturbances, pre-eclampsia, nociception, pain, in particular visceral and neuropathic pain, pancreatitis, neurogenic inflammation, asthma, COPD and micturition disorders such as urinary incontinence. The compounds according to the invention can be represented by general Formula (I) and comprises also the pharmaceutically acceptable acid or base addition salts thereof, the stereochemically isomeric forms thereof, the N-oxide form thereof and prodrugs thereof, wherein all substituents are defined as in Claim 1.