Self-reported individual differences in attachment insecurities (anxiety and avoidance) are sometimes assumed to tap only conscious mental processes, although many studies have found correlations between such measures and responses to the Thematic Apperception Test, the Rorschach Inkblot Test, and diverse laboratory measures of unconscious mental processes. Dreams offer another route into the unconscious, as Freud famously claimed: a route found useful in psychotherapy. In this study, approximately 1000 dreams reported by 68 young adults who kept dream diaries for a month were analyzed using the Core Conflictual Relationships Theme method, and the themes were examined in relation to (a) scores on the Experiences in Close Relationships measure of attachment anxiety and avoidance and (b) stress experienced the day before each dream. In line with attachment theory and previous research, attachment-related avoidance predicted avoidant wishes and negative representations of other people in dreams. Attachment anxiety predicted wishes for interpersonal closeness, especially in dreams following stressful days, and negative representations of self and both positive and negative representations of others, with negative representations being more common in dreams following stressful days.