The invention is directed to benzo[1,4]oxazin-3-one, benzo[1,4]thiazin-3-one and quinolin-2-one Urotensin II receptor antagonists useful in treating or ameliorating a Urotensin-II mediated disorder. More specifically, the present invention relates to certain novel benzo[1,4]oxazin-3-one, benzo[1,4]thiazin-3-one and quinolin-2-one compounds and methods for preparing compounds, compositions, intermediates and derivatives thereof. Pharmaceutical compositions and methods for treating or ameliorating a Urotensin-II mediated disorder using compounds of the invention are also described.