To establish the diagnosis of acute pancreatitis the estimation of amylase in serum and urine, lipase and radio-immunoreactive trypsin in the serum are useful. Lipase estimations are more helpful than measuring amylase values. Trypsin-RIA-tests are increasingly important adults. But in chronic pancreatitis and inborn secretory insufficiencies of the pancreas these methods are less helpful. PABA-test, pancreolauryl-test (PLT), and the estimation of chymotrypsin in faeces are screening procedures, although their results correlate well amongst each other. As compared to the chymotrypsin estimation in faeces PABA test and PLT allow for some semiquantitative estimation of the secretory function and dynamics of the gland. The influence of malabsorption, liver and kidney diseases on these parameters is not yet quite clarified. Besides screening they are undoubtedly of value for judging the course and therapy of cystic fibrosis, Shwachman-syndrome, iatrogenic lesions by cytostatics (immunosuppressives and corticosteroids). Quantitative estimations of fat in faces and the pancreozymin test are no longer of significance.