Alkaline Phosphatase (ALP) is an enzyme found in various tissues throughout the body, with the highest concentrations in the liver and bones. In healthy adults, the majority of ALP in the blood comes from the liver, followed by the bones. Elevated ALP levels are often associated with liver diseases, bile duct obstruction, gallbladder disorders, or bone-related conditions. This test measures the amount of ALP in the blood to help identify potential issues in these areas.