One of the most significant factors, determining effectiveness of any organization is an optimal management of the system, which is perceived as a social organization. Otherwise strategy errors in management potentially undermine the whole system of the organization. Assuming that management based on authoritarian relations may illusionary create an image of swift and effective management however, as it has been proved by definite studies, it actually stiffens the management however as it has been proved by definite studies, it actually stiffens the organization and drives it towards management and functional crisis (Staehle, 1994). On the other hand, management based on humanistic-democratic relations liberates human resources, fosters social self-expression in an individual and a group, awakens creative and inner motivated potential of an individual. Management of educational institutions, being in between management and education/pedagogy, is a specific for scientific research. It should be noted, that a definite input in research work on management of educational institutions on the background of definite organizations does exist. In spite of some positive input in the research on educational management (e.g. Lenz, 1991, Merkys, 2000; Wissinger, 1996; Hopkins, 1998; Zelvys, 1994, 1999) it has to be stated that one sphere of such research management diagnostics (including educational management diagnostics as well) has been neglected. Research problem: The following questions are the background of the research problem--Which theory, tradition should be prioritized in a concrete research of educational management? Which theory is optimal from the standpoint of educational management practice that helps to emancipate the management as a sphere of social practice? IS it possible to find the optimal theoretical priority by empirical way, using non-standardized questioning? Which management theory that is proven in the other cultural environment could be applied without limits in Lithuania? Aim: To test triangulation procedures of the methods and to assess explorative-heuristic effectiveness of these methods in the conditions of a definite diagnostics in educational management research. The background of the research, which is presented in a paper, illustrates one methodological standpoint point. While studying social attitudes and social behaviour of people (here of school heads) the deeper cognition is possible when there are attempts to combine the quantitative and qualitative methods. (Contains 4 tables.) [Abstract modified to meet ERIC guidelines.]