Few otherfacetsofsocial andeconomic life are sopoorly understood and yet so indisput- ablyvital for prosperous development as irifrastructure. Sincetheearly 1980sresearchers and policy makers in various OECD nations have started to readdress the issue ofinfra- structure investments. This renewed interest has been promptedby a varietyofconcerns. One observation was that such investments were declining from levels which mighthave been inadequate in the first place. A second observation was that the timing of these cutbacks in infrastructure spending seemed to roughly coincide with lower rates of growth in outputorproductivity. This raised the intriguing question ofwhetherthe latter might be attributable to the former. Coulditbe thatinfrastructureinvestmentscontrolan economy's rate of productivity growth? The response in many countries has been to initiate theirownresearch in an attempttoverify orrejectthis hypothesis. But the more welearn abouttheroleofinfrastructure anditsrelationships with therest of the economy, the more complicated it seems to be. Time itself is quite difficult to accommodate given the wide variety ofspeeds atwhich differentpartsofaneconomycan adjust.
Because of this inherent complexity, we tend to break the problem down into "bite-sizedchunks", thereby enabling us toisolate the parts ofinterest to us - such as the impact of infrastructure on productivity. In this way we can ignore the complex inter- actions betweenour areaofinterest and the restofour world. By saying ceteris paribus, we overlook many otherkey infrastructuralimpacts like those on theenvironmentandon ouroverall qualityoflife. This distorts the true picture.