The two commentaries reflect a long-standing dichotomy between clinically-experienced researchers who believe clinical personality science should reciprocally inform and be informed by the clinical enterprise (Ronningstam and Russell) and academic researchers who are dismissive of clinical complexity, eschew clinical contexts, and promote their preferred trait model (Weiss and Campbell). The commentary by Ronningstam and Russell reminds us that the clinical presentation and treatment of narcissism is complex and serious. The authors of this rejoinder fully agree. The commentary by Weiss and Campbell is anti-clinical in its stance and fails to effectively connect with the realities of clinical practice. The authors encourage these academic researchers to stop avoiding clinical complexity and clinical contexts, and instead, take advantage of advances in research methods, analytics, and technology to build a truly meaningful bridge between clinical personality science and practice.

The scientific discipline of clinical psychology has witnessed paradigm changes in the prevailing conceptualization of psychopathology and in the rigor of experimental methods to test psychosocial treatments. In parallel, neuroscience approaches to mental illness have become increasingly prominent and technologies to measure psychological constructs over time and across contexts are becoming ubiquitous in psychological research. Altogether, these changes have pushed clinical scientists to incorporate novel research methodologies and analytic approaches. Modern studies of clinical phenomena are often theoretically integrative and assess constructs across levels of measurement, ranging from the molecular to the behavioral. These shifts are fundamental, and necessitate changes in the way modern clinical psychologists design studies, collect data, and draw scientific conclusions. This book is intended to serve as a guide for the next generation of clinical psychologists, who will benefit from greater training in statistics, study design, developmental psychopathology, and multimethod approaches.

At the end of the nineteenth century, Darwinian interests in animal behavior converged with experimental psychology to give rise to systematic research on learning in animals. For the first half of the twentieth century, Ivan Pavlov’s study of conditioned reflexes was a major influence, but many American researchers maintained the behaviorist claim that all learning is based on stimulus–response (S–R) habits. A major critic of this dominant tradition emphasized spatial learning, suggesting that conditioning procedures produce expectancies rather than habits. Another kind of attack on S–R theory concentrated on its claim that learning processes were the same for all species. The comparative approach investigated ways in which, for example, the learning capacities of primates differed from those of rats or even goldfish. Other researchers investigated biological constraints on what animals can learn and the way that learning depends on a researcher’s choice of stimuli and responses, as in the study of conditioned taste aversions. Several key discoveries in the late 1960s laid the foundations for new associative theories of learning and a revival of interest in cognitive processes like attention. These approaches, together with breakthroughs in research on neural bases of behavior, have dominated research on animal learning ever since.