Organizations specifically the airlines industry are increasingly facing the challenges of operational efficiency measurement. During the last years enormous attention has been given to the assessment and improvement of the performance of productive systems. However, literatures show that there are limitations of the existing models to measure efficiency uniformly and exhaustively across the airlines. The problems are due to lack of the technical efficiency measuring model which unifies and integrates different measuring models into a single model.Therefore, this thesis investigates assessment of the operational performance of world major airlines by employing integrated comparative models to address the above problems. In this study, technical efficiency is addressed among many performance issues by using three types of modes of performance measurement: a non parametric one, represented by Data Envelopment Analysis (DEA) and; a parametric one, represented by Stochastic Frontier Analysis (SFA) and the Balance Scorecard (BSC) which is a strategic management tools. Unlike most of the previous studies, this study integrates the BSC concepts into DEA and SFA model. To evaluate technical efficiency of major international airlines, the study use panel of unbalanced data for the year 2007-2014 to make integrated comparative analysis. The research project incorporates seven leading variables and four lagging variables taken from BSC concept to implement into the DEA and SFA. All the three models of performance measurements have their own strength and limitation if they are used alone. But if the three models are integrated and combined together, they would yield better comparative and quality of efficiency assessment. Therefore, the study primarily developed a model beginning from the theoretical framework assumption into building of a unified comparative model of integrated comparative operational efficiency assessment of airlines. The research design and methodology uses secondary data collection i.e. annual reports and business reports of airlines which are collected from the airlines own website. The huge amount of financial and operational data cannot be collected by using primary data collection method as it would make it practically impossible and expensive. So by employing secondary data collection method saves time, money and a panel data can be accessed and generated easily. Hence, from 100 world major airlines population which are ranked by revenue, simple random sampling is used to select 80 samples airlines for this study. First, the BSC identifies the input and output variables. Next, the DEA model ranks the efficiency measurement, identifies the slack variables and benchmarks the airlines. Third, the SFA model identifies technical efficiency, the random error and technical inefficiency. Finally, the technical efficiency estimates obtained from the two techniques are analyzed comparatively. The research makes further analysis of particular case of the Ethiopian Airlines in relation to the most efficient and inefficient airlines and in comparison of the regional analysis. After extensive tests have been conducted, ‘Balanced Frontier Envelopment’ model is developed. According to this model, it is a paramount to measure efficiency with combining the strength of three models together and gives better results than the previous one or two combined models. The developed and integrated strategic model enhances measuring of the operating technical efficiency of airlines. This model benefit the airlines industry in many ways such as minimizing the cost and maximizing profit through managing technical efficiency which lead into the success of the airlines. From the model perspective, therefore, result of DEA model is much higher than the result of SFA model. DEA model is easier to manipulate than the SFA model because the former does not need the functional form while the later requires a functional form. Furthermore, according to the efficiency finding of the study, first, the European regional airlines are relatively more efficient than the rest of regions in the world. Second, the North America regional airlines are the second more efficient regional airlines in the world. Third, the Ethiopian airlines are the most efficient in Africa when we compare among Egyptair, Kenyan Airways and South African Airways. Fourth, high revenue does not necessarily leads to the technical efficiency of the firm. / Business Management / D.B.L. (Business Leadership)