To achieve effectiveness and efficiency in public enterprises, change is needed. Due to the rapid changing global environment and increasing demand for service delivery, continuous change is needed. Changes have been taking place in the Kenyan public sector since 2003. The public enterprises in Kenya, like in most countries in Sub-Saharan Africa, have been characterised by slow and bureaucratic processes that retard organisational performance. Employees and managers in these enterprises have been perceived as not performing as they should. Kenyan public enterprises are important to the economy of the country. They provide social services to the Kenyan population and employ about 654 200 people. The latter translated in a wage bill of 84 378 million Kenyan Shillings (Ksh 80 = 1 US dollar). There is therefore a need to investigate ways to improve individual and organisational performance, collectively viewed as organisational effectiveness in this study, in these enterprises. It is generally accepted that leadership and organisational culture play a critical role in managing the effectiveness of enterprises. In this study, leadership style (transactional and transformational), leadership personality (Machiavellianism, narcissism, masculinity, femininity, individualism and collectivism) and organisational culture (entrepreneurial and market-orientation), strategic management, corporate ethics are investigated determinants of organisational effectiveness. A survey approach was used to collect data from 670 senior executives from 134 Kenyan public (state) enterprises. Two hundred and fifty-six (256) useful survey responses from 53 public enterprises were received. Structural equation modelling (SEM) statistical technique was used to test the hypothesised relationships between the above-mentioned determinants and the dependent variables (individual performance intention and organisational performance). The descriptive statistics of the raw data were also analysed to ascertain the managers’ perceptions about these determinants in the public enterprises. The empirical results revealed that transformational leadership exerts a positive influence on both organisational performance and individual performance intention; that self-deceptive narcissism motivates individual performance intent but decreases organisational performance; that an entrepreneurial, market and strategic management orientation positively influences organisational performance; and that strategy implementation positively influences individual performance intent. In view of these findings, the study concludes that it is critical that leadership styles and leadership personalities be taken into account in leadership recruitment and development process in Kenya public enterprises. Kenyan public enterprises will also improve their organisational performance if they implement entrepreneurial, market and strategic management principles.