Background: Critical care nursing is a specialty which deals with the care of critically ill patients with potential or actual life-threatening illness. The critical illness of the patients and the extensive use of technology to monitor and treat patients, create a complex environment in the critical care units that demands critical care nurses possess specialist knowledge and skills to make the complex decisions needed to care for critically ill patients and their families. Compared to developed countries, where significant resources are invested in critical care environments and specialised training of health professionals, the situation differs in developing countries like Malawi. In the developing countries there are critical shortages of resources and health professionals with critical care training. There are no critical care nurse training programmes in most developing countries as is the case in Malawi. This is against the background of high burden of communicable and noncommunicable diseases which increase the demand for critical care services in the developing countries. In the absence of proper training, the nurses rely on their intuition and basic nursing education to meet the needs of the critically ill patients and their families. This PhD study is premised on documented evidence that critical care nurses in Malawi lack the knowledge and skills required for their practice in the critical care units. The study aimed to explore learning needs of the critical care nurses as a way of informing the development and evaluation of in-service training for the nurses in Malawi. Methodology: A programme planning and evaluation approach using multiphase mixed methods design was applied. The study was conducted at two public tertiary hospitals which were purposively selected. The implementation of the quantitative and qualitative strands in two of the three phases of the study followed the principles of explanatory sequential mixed methods. The phases of the study were informed by Caffarella’s Interactive Model of Programme Planning as follows: Phase 1: needs assessment. Nurses (n=79) in intensive care units (ICUs) and high dependency units (HDUs) self-assessed their competence on the Intensive and Critical Care Nursing Competence Scale (ICCN-CS-1) and a list of 10 additional competencies. An interpretive descriptive design was used in the follow up qualitative strand. Data were gathered through two focus group discussions with the nurses, and key informant interviews with nurse leaders (n=8) and anaesthetists (n=2) on learning needs of the nurses. Phase 2: Development of the training programme. A training programme was developed in consultation with Malawian experts in intensive and critical care nursing (n=4) and one anaesthetist. Phase 3: Implementation and evaluation of the programme. The training programme was delivered to ICU and HDU nurses (n=41) over three days at each hospital. The impact of the training was evaluated through self-assessment on ICCN-CS-1 and the additional competencies at Time 1 and 2, pretraining and post training respectively; and completion of a training evaluation form and interviews with participants (n=8) at Time 2. Quantitative data were analysed using SPSS version 23. Qualitative data were entered into NVivo programme. The data were then analysed manually utilising Thorne’s (2008) steps of analysis. Results: In Phase 1, nurses rated their competence on ICCN-CS-1 as good and excellent (M = 604.97, SD = 55.08). Majority of the nurses rated their competence as poor or moderate on two additional competencies; basic interpretation of electrocardiogram (83.5%; n=66) and analysis of arterial blood gases (83.5%; n=66). Most of the identified learning needs were related to knowledge domain of nursing competence. Analysis of the qualitative data identified three themes, ‘being unprepared’, ‘challenge of limited resources’ and ‘knowing’. Phase 2: A training programme was developed based on the identified learning needs. Phase 3: There was statistically significant increase in the competence score on ICCN-CS-1 from Time 1, pretraining (M = 608.2, SD = 59.6) to Time 2, posttraining (M = 684.7, SD = 29.7), t(40) = 8.8, p <.001 (two-tailed). The mean increase in the competence score was 76.9, 95% CI [59.3, 94.5]. Similarly, there was a statistically significant increase in the overall score on additional competencies from Time 1 to Time 2, p <.001 (two-tailed). The mean increase in the competence score was 11.9, 95% CI [10.1, 13.8]. The overall programme was rated very relevant by 85.4% (n=35) of the participants. Post training interviews showed that the training was well received by the participants. Conclusion: Nurses self-rated their competence on ICCN-CS-1 as good and excellent but the majority rated knowledge and skills on additional competencies as poor in Phase 1 of the study. The results of the subsequent qualitative strand in the same phase revealed that CCU nurses are not adequately prepared for practice in the units. The identified learning needs guided the development of a training programme which was implemented at the two hospitals. The competence scores of the nurses who received the training significantly increased at the end of the training. The study addressed the need for a training programme for CCU nurses, which was implemented using existing structures and resources in Malawi. Recommendations have been made in relation to critical care nursing education, practice, health policy, regulatory body and nursing research.