The success of the Historic Rehabilitation Tax Credits is apparent through the revitalization of many of the USA's inner cities. The tax credit drove a significant amount of capital into real estate projects in some of the country's most destitute yet historic areas. That trend came to end with the Tax Reform Act of 1986. This thesis evaluates the likely impact of the proposed measure to strengthen these tax incentives through a specific case study in Philadelphia's historic Old City neighborhood. The conlusion of this case study is that the Community Revitalization Tax Act of 1990 would improve the after tax returns of historic rehab projects, but that the underlying economics of each project will be more important than in prior years. While tax incentives are a great motivator for guiding private capital, there is no substitute for sound investment fundamentals.