Juan Botella is PhD in Psychology by the Autonomous University of Madrid, where he has developed most of his academic career. He has coordinated a large number of funded research projects. He is the author of numerous papers in national and international journals, as well as various monographs and textbooks. He is a member of several national and international scientific societies, such as the Spanish Association of Methodology of Behavioral Sciences (AEMCCO), the European Society for Cognitive Psychology (ESCOP), the Psychonomic Society (PS), the Spanish Society of Experimental Psychology (SEPEX), and the Society for Research Synthesis Methodology (SRSM). His teaching activity has been developed mainly in the field of Research Methodology, both in undergraduate and postgraduate degrees, in several universities. He is the author of a widely used textbook on Data Analysis and another one on Meta-analysis widely disseminated among PhD students and researchers. He has directed numerous doctoral dissertations, several of which have been awarded with the Extraordinary Doctorate Prize. He developed his research activity in various fields, but it is worth mentioning the experimental study of attention. In this regard, he made a research stay during the 1989/90 academic course with Professor Charles W. Eriksen at the University of Illinois. Some years later, he helped to promote and organize the Scientific Meeting on Attention (RECA) in 1997, which has already held 11 editions. He is a founding member of the Spanish Society of Experimental Psychology (SEPEX). He has also collaborated in evaluation research projects, focusing mainly on the objective evaluation of personality, as well as on the development of mathematical models of behavior. His main line of investigation is on the meta-analysis methodology. He gives courses in the Interuniversity Master in Methodology of Behavioral Sciences (UAM, UCM, UNED). He has contributed to disseminate this methodology through short courses in several national universities. He has directed several research projects and he is the author of a textbook (Meta-analysis in Social and Health Sciences). He is the author of several meta-analyses on issues related to different fields of psychology. He has also published several papers in which he presented new ways to apply this technic to different analytical contexts. The most recent ones refer to the synthesis of independent estimates of the internal consistency of a test, the meta-analysis of valuation studies of binary classification instruments with heterogeneous references, or the recovery of missing information in studies using an experimental framework in line with the Theory of Signal Detection.