Health care delivery systems face different obstacles when engaged in health information systems implementation. The success of such systems is dependent upon many factors. These factors must be identified and carefully considered to ensure successful system implementation. This study investigates possible factors affecting successful information systems implementation in the Kuwaiti health care delivery system within the public and private sectors. The research was designed as an exploratory study in which qualitative and quantitative approaches were used. In the first stage (qualitative) a focus group was formed and then a semi-structured interview was administered. Themes that emerged from the interviews were used to develop a questionnaire that was used in the second (quantitative) stage of the study. The study covered stakeholders from the public and private sectors in Kuwait. The qualitative part investigated the impact of certain factors on system implementation successfulness. Based on interviewees' responses, three major themes emerged. Those were used to develop the questionnaire which was used in the quantitative part of the study. The questionnaire was aimed at describing the perception of the stakeholders to the preset factors with regard to their effects on the success of implementation in their respective organisations. From both sectors, a sample of 493 respondents was randomly 2 selected. The response rate for the questionnaire from the two sectors ranged from 59% to 72% depending on the stakeholders' group of respondents. When examining the findings of the questionnaire, the perceptions of the top management in the public sector at MOH and Al-Amin hospital were similar toward most of the factors studied. However, they were different from those of the end users. On the other hand, the perceptions of the top management and the end users were similar in the private sector. . The top management in the public sector (MOH and Al-Amin hospital) ranked the following factors in this order as the most important factors that affected successful health information systems implementation in the public sector: Accountability; Resistance to change; Organisational diversity; Organisational stability; and Incentives. The end users in the public sector ranked the following factors as the most important factors that affected successful health information systems implementation in the public sector: Lack of end user involvement; Insufficient planning; Training; Incentives; and Uncertainty of benefits. Both the top management and end users of the public sector ranked "Incentives" as one of the most important factors that affected successful health information system implementation, but this was the only point of agreement between them. In the private sector, the top management ranked the following factors as the most important factors that affected successful health information systems implementation: Resistance to change; Ease of usage; Competition; Incentives; and Compatibility. The end users in the private sector ranked the following factors: Ease of usage; Timeliness; Incentives; Relative advantage; and Competition. The top management and end users in the private sector concurred over the importance of the following factors: Ease of usage; and Competition. In conclusion, both the public and private sector participants (top management and end users) ranked `Incentives' as one of the most important factors that affected successful health information system implementation, while the top management in both sectors (MOH, Al-Amiri and Al-Mowasat hospitals) ranked `Resistance to change' as one of the most important factors that affected successful health information system implementation. In all, the results show that the primary factor affecting successful implementation of health information system regardless of the sector and the employment category is `Incentives', followed by `Resistance to change'. The information produced in the current study was used to produce recommendations on the successful future implementation of health information systems in Kuwait. The recommendations are based on empirical findings, and are to be respectfully commended to strategists concerned with improving health care delivery system in Kuwait. 4 The first and most obvious recommendation regarding future research would be a replication of the same study, but with the inclusion of more comprehensive attributes such as: 1) Vendor services (e. g. hardware performance, expansion and growth potential, ease of modification, interface capabilities, ease of installation, and upgrading capabilities. 2) Vendor selection factors (e. g. vendor reputation and company philosophy, system pricing, and vendor resources. 3) Patient satisfaction with the system benefits. The second recommendation is to use the same organisational, cultural and user satisfaction factors to examine health information systems implementation in a specific facility such as an Army or Police hospital versus a public hospital.