While a limited amount of research has focused on client loyalty in wider professional services, none has been carried out specifically in respect to construction professional services (CPS). A review of the wider professional service literature identified a number of key candidate loyalty antecedents. Thematic analysis was undertaken on semi-structured interview data obtained from 20 client and CPS supplier participants operating in the West Midlands (UK). The results were used to refine a literature-derived model of CPS client loyalty. Several modifications were made to themes and sub-themes in the light of empirical data. The results obtained will form the basis for a future quantitative phase of research which will determine the extent to which the findings of this qualitative research generalise to the wider population.