Abstract: The economy of Saudi Arabia depends on the human resource development and competency and teamwork are two important aspects that can give organisations a competitive advantage. The main purpose of this study is to investigate the relationship between employee competency, teamwork and organisational performance within private sector organisations in Saudi Arabia. Evaluation of the proposed model was done through examining data collected by a survey questionnaire from 170 valid respondents. The analysis looked at the relationship between the variables of the proposed model, including Confirmatory Factor Analysis (CFA) and Structural Equation Modelling (SEM) via AMOS. The goodness of fit of the proposed model to the data, explained 69% of the variance in organisational performance. The findings of the multivariate analysis demonstrated three main results. First, employee competency has a positive impact on teamwork and organisational performance. Second, teamwork has great influence on organisational performance. Third, the bootstrapping analysis showed that teamwork mediates the relationship between employee competency and organisational performance. The theoretical and practical implications are also discussed.