Building a therapeutic alliance with a patient with pathological narcissism or narcissistic personality disorder is a challenging process. A combined alliance building and diagnostic strategy is outlined that promotes patients’ motivation and active engagement in identifying their own problems. The main focus is on identifying grandiosity, self-regulatory patterns, and behavioral fluctuations in their social and interpersonal contexts while engaging the patient in meaningful clarifications and collaborative inquiry. A definition of grandiosity as a diagnostic characterological trait is suggested, one that captures self-criticism, inferiority, and fragility in addition to superiority, assertiveness, perfectionism, high ideals, and self-enhancing and self-serving interpersonal behavior. These reformulations serve to expand the spectrum of grandiosity-promoting strivings and activities, capture their fluctuations, and help clinicians attend to narcissistic individuals’ internal experiences and motivation as well as to their external presentation and interpersonal self-enhancing, self-serving, controlling, and aggressive behavior. A case example illustrates this process.