There has been a substantial rise in the number of students enrolling in part-time taught postgraduate awards. This study investigates the reasons or motivation for students to spend significant amounts on tutorial fees and find time alongside work, family and social commitments to take a taught postgraduate award. Data were gathered through interviews with 21 part-time students in taught postgraduate programmes in Hong Kong. Students all held several motives for studying, so the outcome was a framework for explaining multiple interacting motives. Main categories of motivation were related to qualifications, current career, potential future career, interest, perpetual students and professional and social networks. Individual students displayed varying degrees of these motivations and the sub-categories of them. Students were able to specify their needs in terms of advanced specialised study, so enrolment satisfied a need for continuing professional development. The rise in taught postgraduate enrolments, in search of advanced specialised knowledge, seems set to continue as undergraduate degrees become broader and more attribute-oriented and the knowledge explosion makes it harder to reach the frontiers of knowledge.[Copyright of Studies in Continuing Education is the property of Routledge. Full article may be available at the publisher's website: http://dx.doi.org/10.1080/0158037X.2011.646979]