There is every indication that most of our flavor preferences and dietary behaviors are learned. Despite this, we know very little about the underlying mechanisms. This paper considers reasons why this might be the case. In addition to considering particular methodological issues and the potential relevance of a 'critical developmental period', emphasis is placed on the need to resolve whether learning results from an implicit or an explicit process. Addressing this issue has important implications for the way that studies should be designed. It also leads to one of two diametrically opposite conclusions. Either behavior is governed by a rather rare form of automatic and involuntary associative learning, or otherwise, it should be regarded as non-automatic and subject to attentional and other constraints associated with most other forms of learning in humans. This latter proposition invites speculation that learning might also be governed by more complex representations (beliefs and attitudes) associated with the foods and flavors that are presented in learning studies. More generally, an analysis of this kind is important because it has the potential to explain differences that might underpin particular aberrant eating habits. (c) 2005 Elsevier Inc. All rights reserved.