The purpose of this study is to prove that the optimization of parameters of a given healthcare system unit according to sustainability principles leads to higher efficiency. In this study, Department of Medical Biochemistry at the Laboratory of Medical Biochemistry of the Zabok General Hospital was chosen to represent a healthcare system unit. The actual research for this thesis was performed at the University of Zagreb School of Medicine Andrija Stampar School of Public Health from 30.03.2014 to 30.09.2015 (duration of study – 6 months). The hospital in Zabok was chosen for the current study because it is one of the leading institutions in Croatia and the laboratory where the study was performed occupies fully equipped premises with plenty of materials, innovative equipment and professional staff, accordingly presenting sufficient components for the present research. Quantitative and qualitative methods were employed to reach our general aim of testing the hypothesis that the optimization of input parameters leads to higher economic efficiency. The study was performed according to the working plan of data acquisition and consisted of Initial Phase, Modelling phase and Analytical phase with the subsequent data processing. We used methods such as Life Cycle Assessment, structured interview, computer modelling, and direct content analysis. Life Cycle Assessment methodology was effectively adopted for the purposes of health care system unit analysis and it is the first study of LCA implementation in health care in Croatia. In the duration of the study the given inputs and outputs such as chemical reagents, solutions, technical equipment, conditions of the working environment, quantity of different types of waste over a period, working hours, expenses were calculated. Also the interviews with medical staff with subsequent transcription and Direct Content Analysis were introduced with the aim of obtaining a deep-level qualitative data. Modelling and deep-level computer data analysis was performed, in order to find parameters that could lead to optimization of the unit. It shows an opportunity to perform computer based Data analysis of parameters inside the boundaries of a Laboratory. After precise analysis we distinguished the key parameters that may lead to optimization the whole system. We labelled them as Hard and Soft. The results obtained confirmed our initial hypothesis. Recommendations are given. In addition, in the course of the study, the importance of the mental condition of the staff and relationships among co-workers, which positively or negatively affect the performance of their professional tasks were revealed. Introduction of LCA to healthcare refers to one of the building blocks of the Europe 2020 Strategy – “Roadmap to a Resource Efficient Europe” and proposes ways to increase resource productivity and to decouple economic growth from both resource use by units and environmental impacts. The permanent scarcity of resources, materials and the emphasis on cost-saving procedures in the social sphere lead us to try to find effective means for the optimization of economic and environmental performance of a healthcare. Inside the proposed framework the identified parameters may lead to the creation of new models and techniques for the final units’ optimization. Life Cycle Assessment methodology should be successfully applied to analysis of healthcare system units (e.g. department, laboratory, hospital, ambulance, and operating theatre), the study of a life cycle of a single process, the efficiency of medical staff as well as for the analysis of the performance of the healthcare system of a particular region or a whole country. Furthermore, the rising social responsibility, corporate social responsibility and Life Cycle Management will be drivers for the development and widespread application of such methods to processes and activities of healthcare institutions worldwide. As a result, it would be of great importance to develop and implement an effective public healthcare system model based on relevant, meaningful, robust results of and principles for the careful use of resources, improvement of patient recovery and economic efficiency of units. As a result, public health and health care sectors may become sustainable and reliable social partners with a high level of responsibility encouraging committed and motivated employees and satisfied patients.