This study examined the influence of top management teams of financial institutions, tourism enterprises and manufacturing firms on these firms’ performance. Informed by Hambrick’s Upper Echelons Theory, various studies have examined the relationship between top managers and organisational performance and the findings have been only been contentious but also offered contradictory conclusions. A total of 363 managers from the three sectors of the economy were surveyed in Dar es Salaam, Arusha, Mwanza, and Kilimanjaro using a structured questionnaire. Descriptive statistics (Frequencies, Percentages, Means, and Standard Deviations) and inferential statistics (Structural Equation Modelling) were employed to establish the existing relationships between demographics and entrepreneurial orientations of managers and the firms’ performance. The findings show that management demographic characteristics and entrepreneurship orientations bear a significant influence on the firms’ performance. It is, therefore, recommended from these findings that a mix of the top management should take into account age limit, experience and a desirable socio-economic background.