Ownership is an innate perception of individuals which could manifest in their possessive behaviours. Owners of property are inclined to extend a sense of self to their possessions, demand a right to control them and use them as a tool with which to interact or negotiate with other people. Clarifying ownership of knowledge is difficult in terms of whether the knowledge in question should belong to an individual following privacy rights or it should belong to an organisation following intellectual property rights (IPR). Furthermore, conflicts occur between developed countries which have a stronger culture for the IPR than developing countries do. Studying knowledge ownership helps to understand these differing viewpoints. Previous works found that knowledge ownership influences the intentions to share knowledge. Nevertheless, little research has been done to explore the knowledge ownership concept particularly in a cross-cultural context. This thesis suggests that cross-cultural research is an appropriate approach to conduct a study on knowledge ownership because ownership perceptions vary from cultures to cultures. The work of Ekweozor (2008) is extended in this study to include a comparative study between the UK and Thailand to validate previous findings. Furthermore, knowledge ownership concept, its influencing factors and its relationship with knowledge sharing intentions are examined. Secondary data in the UK context were adopted from Ekweozor (2008)'s work. The Thai version questionnaires translated from her English version were distributed to collect data in the Thai context. The results show that knowledge sharing intentions vary according to types of ownership perception which include individual, organisational and collaborative ownership. Employees who perceive organisational ownership tend to have more intention to share knowledge than the others. In contrast, employees who perceive individual ownership tend to have less intention to share knowledge than the others. In addition, the results reveal that contextual factors including nationality and sector, and conditional factors including types of knowledge, the work environment and personal characteristics, influence what individuals believe about knowledge ownership. Moreover, apart from the mediating role, it is found that knowledge ownership also has a moderating role between the work environment and knowledge sharing intentions. It should be noted that the study was conducted only in the UK and Thailand thus it may not be able to generalise to other countries. Despite this limitation, this study emphasises that knowledge ownership perception is a crucial factor that influences knowledge sharing intentions in organisations. In addition, knowledge ownership could mediate and moderate the relationship between the work environment and knowledge sharing intentions. It is also recommended that contextual factors should be considered when conducting a study on knowledge ownership perceptions because each context differs in many respects such as cultures, regulations and the work environment. Therefore, in order to strengthen and validate research findings in this area, cross-cultural research is an important strategy. Overall, this study theoretically and practically contributes to and advances knowledge of knowledge ownership by providing empirical evidences and implications for researchers and practitioners in a cross-cultural context.