This volume contains papers presented at the joint 16th Annual Conference on Learning Theory (COLT) and the 7th Annual Workshop on Kernel Machines, heldinWashington, DC, USA, duringAugust24 27,2003.COLT, whichrecently merged with EuroCOLT, has traditionally been a meeting place for learning theorists. We hope that COLT will bene't from the collocation with the annual workshoponkernelmachines, formerlyheldasaNIPSpostconferenceworkshop. The technical program contained 47 papers selected from 92 submissions. All 47paperswerepresentedasposters;22ofthepaperswereadditionallypresented...