This invention concerns substituted oxa-diaza-spiro-[5.5]-undecanone derivatives having neurokinin antagonistic activity, in particular an NK1 antagonistic activity, an NK3 antagonistic activity, a combined NK1/NK2 antagonistic activity and a combined NK1/NK2/NK3 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, chronic obstructive pulmonary disease (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.