Dr. David has significantly contributed to the assimilation of cognitive science principles in the clinical field, endorsing a ''scientist-practitioner'' and an ''evidence-based'' approach in psychology in general, and in the clinical field in particular. His more specific contributions are related to the development of the theory and practice of rational-emotive & cognitive-behavioral therapies (CBT/REBT) in the context of clinical cognitive neurosciences (basic research), and to studying their relevance (translational and applied research, including development & innovation) in cancer research and the mental health field.

His research results brought Professor David the Aaron T. Beck Award and the Albert Ellis Award of the International Institute for the Advanced Study of Psychotherapy and Applied Mental Health. In 2004 he was appointed guest editor by the Journal of Clinical Psychology to develop a special issue titled: "Cognitive revolution in clinical psychology: Beyond the behavioral approach," presenting the state-of-the-art regarding the impact of the cognitive revolution on the clinical field. As founding editor of the Journal of Cognitive and Behavioral Psychotherapies (abstracted: SSCI/Thomson ISI; SCOPUS; PsycInfo; IBSS and full text: EBSCO; ProQuest), a journal focused on evidence-based practice, he has supported the evidence-based approach in the clinical field. For his merits in research and education, in 2008, he was knighted by the President of Romania (Decree 201 of 17/01/2008) in the National Order of Knights for Merit.

Dr. David current research is focused on the role of cognitive mechanisms, both explicit (e.g., autobiographical memory) and implicit (e.g., implicit memory; priming) in generating subjective/emotional (cognition-emotion relation), behavioral, and psycho-physiological human responses, more specifically, on the role of (a) rational/functional and irrational/dysfunctional beliefs and (b) response hopes and/or expectancies on various psychological and medical outcomes related to cancer and mental health. When clinical trials are used as research instruments the analysis employed is typically multilevel, concerning: (1) outcomes (i.e., efficacy and/or effectiveness); (2) theory/mechanism of change; and (3) economical aspects (e.g., cost-effectiveness, cost-utility). A specific research interest is related to the theory and practice of cognitive hypnosis/hypnotherapy as part of the cognitive neuroscience paradigm.