What established his international reputation in the area of mindfulness research among peers were his research contributions around mindfulness in psychotherapeutic practice. After many years of phenomenological research, he, together with Prof. Dr. Marius K. Nickel/Bad Aussee, Austria, and Prof. Dr. Loew/Regensburg, Germany, presented groundbreaking pioneering studies (2006a, b; 2007a, b; 2008) which were the first ones to document the positive impact of mindfulness on the part of the psychotherapist with regard to treatment results. The Clinical Handbook of Mindfulness by F. Didonna (2009), among others, identifies these studies as the beginning of research in this field (also cf. e. g. Walach 2008). Together with Prof. Nickel, L. J. Grepmair also authored the very first book in this area of expertise, a monograph in which the authors also were the first ones to describe psychotherapy as a Zen healing modality (Grepmair & Nickel 2007a).

It was L. J. Grepmair's confrontation with his own challenges in practicing meditation/mindfulness which led him to develop the AwareAidOn approach and device.