Transforming the Internal World and Attachment reviews and discusses four theories about what makes psychotherapy effective across forms of treatment, treatment settings, and diagnostic categories: mindfulness, mentalization, psychological mindedness, and the attachment relationship. Geoff Goodman offers some provisional hypotheses about therapeutic effectiveness and suggests some ways of testing these hypotheses empirically, using sophisticated assessment instruments that measure psychotherapy process and outcome. Managed-care companies are withholding reimbursements for treatments not considered "empirically supported." Instead of engaging in horse races with randomized controlled trials (RCTs), Goodman suggests that we need to establish an empirical basis for the therapeutic effectiveness of all forms of treatment, move beyond examining common factors such as the therapeutic alliance, and turn our collective attention to common factors that psychotherapy researchers often erroneously promote as specific factors. Perhaps these so-called specific factors produce therapeutic change regardless of the brand-name treatment packages through which they are typically delivered. These specific factors might also work better for particular groups of patients with specific problem areas such as affect dysregulation and impulsivity. In Volume I, Goodman explores the empirical and clinical bases of these specific factors and outlines their various influences on psychotherapy process and outcome.