From the back of the book:
At last some means of combatting the ultimate undead, vampires, have found their way into print. Within these pages, Dr. Rudolph Van Richten shares his vast background as one of Ravenloft's most formidable lore masters and vampire hunters. Decades of research and experience have been compiled into discussions which define the very nature of those "kings of the undead," and help put them at a disadvantage to mortals, whom they consider to be "mere cattle."
Dr. Van Richten has detailed vampiric powers, weaknesses, feeding and sleeping habits, even their varied relationships with others of their own kind. Old myths are dispelled, new facts are uncovered, and the experiences of both vampires and those you hunt them are recorded for your safety and enlightenment.