Introduction

The integration of land use and transport planning is one of the most important topics in urban and regional planning. Accessibility is believed to provide a useful framework for the design of integrated land use and transport policies. The consideration of a myriad of concepts and tools to address these topics are increasingly common in academic research, a result of the last decades of development of fast and cheaper computation, along with the development of database technology and the emergence of new, larger and more reliable datasets. However, the effective use of these concepts and tools in the professional planning practice did not follow the same pace of development, and there is today a significant gap between the advances in knowledge on accessibility and its effective application in the professional practice. The literature on Planning Support Systems (PSS) identifies the dichotomy between supply and demand of PSS, such as accessibility instruments, as the main reason for this gap of underutilisation. On the one hand, planning practitioners (the potential users) are, to a great extent, unaware of the very existence of instruments or, if familiarised with them, are quite inexperienced with their use. The value and potential of the instruments are not recognised, resulting in low intention to use them. On the other hand, developers of PSS frequently have little awareness of the demand requirements. The effective use of PSS is currently suffering from a “rigour-relevance dilemma”, with developers mainly concerned with rigour while users are mainly concerned with relevance. The increasing complexity of planning (in addition to current technological developments, especially in computer sciences) has motivated the development of more capable (but also more complex) PSS.