The thesis is a study of property occupier displacement generated by the supply of new office and industrial accommodation that has been promoted or assisted by property-led regeneration policies. A review of literature revealed that there had been little in-depth investigation of the phenomenon of occupier displacement and the filtering effect associated with it. A flow model was developed to illustrate the incidence of occupier displacement and the process of property market filtering. There are two main strands to the research (see Figure 1.1), firstly an exploration of the property chains generated by the displacement of office and industrial occupiers in response the supply of new accommodation, and secondly, an investigation of the reasons why office and industrial occupiers relocate and how they determine where to move to. Three phases of research were employed to record the displacement generated by twenty public sector assisted office and industrial developments in the Tyne and Wear conurbation. Occupiers of twenty developments were identified by site inspections and a total population questionnaire survey was undertaken, complemented by a telephone survey, to record the status and origin of over 500 property occupiers and allow the property chains to be pursued. The chaining exercise revealed the scale of displacement or relocation and the outcome of the resulting chains. The origin of first move occupiers and chain-ends was plotted to reveal their spatial distribution. The research recorded that over half of all occupiers had relocated and over a third of chains generated by such moves, resulted in vacant property elsewhere in the conurbation. Structured interviews with 29 office and industrial occupiers were undertaken to investigate their locational decisions and the factors that influenced their outcome, the results of which were triangulated with the earlier research phases to reveal ten key themes that fundamentally determine such decisions. The originality of the research is the scale and rigour of the chaining survey, the mapping of the spatial distribution of the origin of occupiers and the chain-ends, and the pursuit of understanding of how occupiers respond to the availability of new accommodation. The scale occupier displacement, generated by new office and industrial accommodation, is significant, but by stimulating property market excitation and vacancy a filtering effect is set-up that can generate positive benefits to a local economy by allowing occupiers to expand.