Theme convergence is the linking of seemingly unrelated problem domains as they advance through assimilation stages-a developmental sequence of cognitive and affective changes through which problematic content is hypothesized to pass during successful psychotherapy. Theme divergence is the contradiction or conflict of solutions to different problems, so that progress in one domain leads to stagnation or regression in another domain. An intensive qualitative method called assimilation analysis was used to examine theme convergence and divergence in a successful psychodynamic psychotherapy with a 20–yr–old female patient. Because specific problems often fail to progress monotonically, even in successful psychotherapy cases, it is suggested that clients' problems cannot be resolved in isolation; instead, they may influence each other toward resolution or stagnation in complex and unpredictable ways.