The article addresses those aspects of comprehensive studies which can rightly be considered to number among the most relevant and potentially rewarding problems of forensic science. Until now, neither the concept and structure of a comprehensive study, nor its status and methodology have been the subjects of independent consideration in the legal literature, and were considered only in connection with the analysis of the concept of a comprehensive investigation. Establishing the parameters of expert practice allowed the authors to identify some significant features of comprehensive studies, including their analytical nature, complexity of sources and their combined assessment, and to identify the methodological approaches underlying such research, representing a kind of tool for the synthesis of independent portrayals of complex research in a single and at the same time multidimensional model of forensic science. The empirical and theoretical grounds identified by the authors helped to determine the structure of comprehensive research. Its basic elements are: multiple subjects, a single integral objective, an interdisciplinary task, a specialized program-target complex and a comprehensive expert synthesis. It is concluded that this structure, being invariant for any of the different forms of comprehensive research, reflects its main features and has a pronounced general scientific orientation.