The Greater Cairo Metropolitan Area(GCMA), with more than 19 million inhabitants, is host tomore than one-fifth of Egypt's population. The GCMA isalso an important contributor to the Egyptian economy interms of GDP and jobs. The population of the GCMA isexpected to further increase to 24 million by 2027, andcorrespondingly its importance to the economy will alsoincrease. Traffic congestion is a serious problem in theGCMA with large and adverse effects on both the quality oflife and the economy. In addition to the time wastedstanding still in traffic, time that could be put to moreproductive uses, congestion results in unnecessary fuelconsumption, causes additional wear and tear on vehicles,increases harmful emissions lowering air quality, increasesthe costs of transport for business, and makes the GCMA anunattractive location for businesses and industry. Theseadverse effects have very real and large monetary andnonmonetary costs not only for the economy of the GCMA, butgiven its size, for the economy of Egypt as well. As thepopulation of the GCMA continues to increase, trafficcongestion is becoming worse and the need to address thiscongestion is becoming more urgent. In recognition of theseriousness of the problem of traffic congestion, and uponthe request of Government, primarily the Ministries ofFinance, Transport, Housing, and Interior, the World Bankfunded an investigation into its magnitude, causes, andpotential solutions in the GCMA. This report documents theresults of the study. The results of this study should be ofinterest to policy-makers and practitioners in the GCMA, theEgyptian Government, other cities facing similar problems,and international financial institutions.