Many methodological and ethical accounts of fieldwork become sanitised and smoothed over particularly because they tend to be written several months after the fieldwork has taken place. They often lose the immediacy and emotional impact of the fieldwork, which is why a field diary can be essential. But why do we tend to keep our field diaries to ourselves? Why are we so apprehensive about being open and honest, revealing direct extracts from our field diaries? This paper explores the role and use of field diaries (as opposed to field notes based on observations) in relation to the often hidden struggles of fieldwork. It argues that guilt, apprehension, fears and worries are legitimate, common and even useful experiences of fieldwork. Key issues which emerge in the field diary extracts from my research in rural Bolivia include practical difficulties, emotional and intellectual concerns, and feelings of cultural and academic guilt. It is based on a follow-up study with participants from my PhD research ten years previously. This paper contributes to methodological debates by exploring how we might use field diaries more explicitly to examine the ways our personal challenges and emotions impact on the research process and outcome.