Urban areas are constantly changing as they expand into new territory or existing areas are re-developed.
Infrastructure investments are key components for successfully implementing these changes.
However, the planning and analysis of such investments is complex.
Typically, they are strategic and long-term in nature as they involve large capital expenditures designed for many years of service.
The evaluation of these investments requires the explicit consideration of multiple, conflicting and incommensurate criteria as they have important social, economic, and environmental effects that impact various stakeholders differently.
These decisions also have important spatial implications as many of their costs and benefits are distributed spatially.
Consequently, they have differing impacts on several stakeholders depending upon the type and location of the investments, and upon the citizen groups affected.
The appraisal of alternative urban plans involves the analytical and systemic determination of all the factors influencing the multidimensional value of courses of action, supported in clear principles and using well-defined criteria.