In the 20th Century, Brazil rapidlyurbanized and is now not only an urban nation but ametropolitan one. Brazils sprawling regioes metropolitanas(metropolitan regions, or RMs, which are municipal clusters)are now home to almost 50 million people and much of thecountrys economic vitality. The RM spatial level and itssupporting governmental institutions have thus becomecritical to Brazils future development. While challengesremain for tackling deprivation in rural areas, poverty inBrazil is now predominantly urban. More than six in 10Brazilians in extreme poverty were living in urban settingsas of 2012. Of these, over a fourth was concentrated in the10 largest RMs.