Marriage is challenging, even as the reasons remain mysterious to most people. In order to improve on the results obtained with Couple Therapy 1.0, we need to understand the challenges and impediments that make intimate relationships difficult and so frequently turn love into virtual war. These challenges can be subsumed under three categories: personal challenges due to problematic expectations, “human nature,” and immaturity; interpersonal challenges due to inevitable differences/incompatibilities and the need to settle conflicts; and external challenges (stressors).1 These categories are not entirely orthogonal since they overlap and influence one another. For example, some unrealistic expectations about marriage are a type of emotional immaturity that limit a person’s ability to manage conflict. Nonetheless, the categories used here are easily recognizable and practically useful. We will want to keep them in mind as targets for the interventions to be described in later chapters.