A cold night in the city center of Williston, N.D. Law enforcement agencies are concerned that rapid changes in the region have created conditions conducive to organized crimes like sex trafficking. Annie Flanagan/for NPR hide caption

itoggle caption Annie Flanagan/for NPR

The small streets of Williston, N.D., are bustling with trucks early in the morning. Annie Flanagan for NPR hide caption

itoggle caption Annie Flanagan for NPR

Gas flaring near Highway 85 southwest of Williston. Analysts estimate that almost 30 percent of the gas being produced in the state is burned off. Jeff Brady/NPR hide caption

itoggle caption Jeff Brady/NPR

A drilling site rises from the middle of farmland near Fairfield, N.D. Many farmers and ranchers are profiting from the state's oil boom, but others complain that drillers are interfering with their business. Jeff Brady/NPR hide caption

itoggle caption Jeff Brady/NPR

Ritter Brothers, a jewelry shop in Williston, N.D., sells novelties that might appeal to those benefiting from the region's recent oil boom. Annie Flanagan for NPR hide caption

itoggle caption Annie Flanagan for NPR