Spatial planning in the Netherlands had its heyday in the 1970s. That
was the decade of rational systematic planning and a nationwide covera
ge of all aspects of land use by all sorts of strategic, tactical, and
operational plans. It was also the decade when implementation issues
reached the top of the political and academic agenda. The first genera
tion of implementation and plan-evaluation studies led us to believe t
hat, on the whole, 'performance' was poor. Since then, policymakers an
d academics have both worked on trying to solve this problem. The pape
rs in this issue all deal with this question of performance. This intr
oductory paper gives a broad outline of the questions.