The thesis explores the role of academic education in police professionalisation. Due to its high complexity, specialisation and status, detective work is well-suited for illustrating these developments and the practical and symbolic benefits they can bring to the police and policing as a whole. The overall approach of thesis is iterative. Literature from police studies and sociology of professions provides the conceptual and theoretical framework for the empirical data of 24 semi-structured interviews conducted with 14 police national training coordinators and local police trainers. The increasing academisation of police training and the formalisation of the police-academia relationships suggest police professionalisation has reached a tipping point. This is seen in the current investigative skills training in England and Wales, which is characterised by growing centralisation, standardisation, and emphasis on formalising the professional knowledgebase of investigations and policing - a trend which the Professionalising Investigation Programme exemplifies. While the police (including the investigative specialism) can be shown to display many of the qualities of professions, it has lacked the level of instructional abstraction characterising other professions, typically provided by higher education and, crucially, leading to externally recognised qualifications. Developing academic police education is not without its challenges, chief among them the perceived epistemological and cultural divide between the 'two worlds' of police and academia. A successful transformation requires careful consideration of the content and format of the arrangements, investment, support, acceptance and engagement from police, academia and government, and a simultaneous change to cultural dispositions (habitus) and internal and external structures (field). This is worth the effort as a number of practical and symbolic benefits of police academic education can be identified. It has the potential to improve the quality of service by deepening police knowledge and understanding and facilitating community-oriented approaches. More importantly, academic education bestows a rich cultural capital, strengthens and legitimises police expertise, market monopoly, and status in the eyes of the public, other professions and the government. It enables the survival of the profession, giving it the tools to prevail in conflicts over competence and the right to define and interpret policing and its social context. In summary, police professionalisation via academic education can be explained in terms of agency and structure both; as a deliberate occupational upgrading spurred by social and economic aspirations and aimed to reconceptualise and relegitimise policing; and as an inevitable reaction to wider changes and a deeper ontological shift taking place in the society.