The use of antihypertensive agents in combination is common. To decrease the pill burden, lower the prescription costs and improve patient compliance; combination antihypertensive therapies compile two or more active drugs. Thiazide diuretics are frequently recommended as one of the first-line therapy for the treatment of hypertension in combination with other class of antihypertensive drugs, i.e. angiotensin-converting enzyme inhibitor, angiotensin receptor blocker, calcium channel blocker and beta-blocker. The book demonstrates strategies employed in simultaneous analysis of amlodipine, olmesartan, atenolol, telmisartan, hydrochlorothiazide and propanolol in combined dosage forms for treatment of hypertension. This book is suitable as a reference book for postgraduate and doctoral research scholars. The book can be considered as a guide to the beginners for HPLC method development and validation.