Solving problems is the motivating force behind many scientific endeavours. A student’s ability to solve problems is a key to their academic success. Problem-solving skills developed during a degree course are of significant value to graduate employers and therefore need to be valued significantly by educators and learners. This thesis describes the investigation into the factors that influence undergraduate chemistry students’ abilities to develop the problem-solving skills they require for success in their undergraduate studies and beyond.Quantitative data was gathered from chemistry undergraduates for three cognitive variables thought to influence academic performance. Context-rich open-ended problems were developed in order to assess students’ ability to solve more complex problems. Performance data was gathered from open-ended problem-solving sessions alongside performance data from assessments within a chemistry degree course, including final degree scores. The quantitative data was used to identify any relationships between the students’ cognitive abilities and academic performance.Qualitative research investigated the variety of approaches students take towards solving open-ended problems and also gathered data on students’ attitudes towards and experiences of the use of context-rich open-ended problems.The results show that chemistry students’ mental capacities and disembedding abilities have an impact upon their ability to solve complex open-ended problems. The skills required to solve complex open-ended problems were identified as being different skills to those required to solve the algorithmic problems found to be common elements of assessments used within undergraduate chemistry degrees.The qualitative research revealed details of students’ approaches to open-ended problem-solving and a shift in attitudes towards a more positive view of such activities. Approaches to problem-solving were identified as novice, transitional and expert. Students were also found to be able to reflect upon their learning experiences. They enjoyed the experiences and saw the value of them despite finding them challenging.The implications of the findings are discussed and recommendations for further work are made