Features of dynamical systems thinking can illuminate insufficiently recognized levels of psychoanalytic process. A central aspect of dynamical models is that changes in complex systems are unpredictable and arise out of the interaction of elements. Examination of the moment-by-moment micro-foreground, or local level, of psychoanalytic sessions led to the conclusion that indeterminacy and surprise are inherent properties of intersubjective systems. This indeterminacy, or sloppiness, comprises several interrelated features of the dialogue: “fuzzy” intentionalizing, unpredictability, improvisation, variation, and redundancy. Audiotaped transcripts of two analytic sessions illustrate how these sloppy features generate unpredictable and potentially creative elements that contribute to psychotherapeutic change.