Assessment of severity and prognosis in acute pancreatitis was origina
lly driven by clinicians' needs for the prediction of outcome, togethe
r with the requirement of researchers For objective measurement of sev
erity. Evaluation of the multitude of competing systems has been hinde
red by varying definitions of severity, incomplete reporting and a lac
k of comparative data. Although clinical assessment, Ranson and Glasgo
w scores remain predominant, the recent literature reflects how needs
have changed, as a result of improved understanding of the biological
events underlying attacks and technological advances. The Atlanta Inte
rnational Symposium should provide a suitable framework for progress.