A Salvadoran migrant holds a slingshot in Mexico in July 2010. From 2009 to 2014, Michelle Frankfurter photographed Central American migrants traveling through Mexico en route to the United States.
A border fence separates San Diego and Tijuana, Mexico, in August 2012.
A Honduran migrant at a shelter in Ixtepec, Mexico, in June 2009.
Pants hang at a migrant shelter in Tenosique, Mexico, in January 2014.
This Honduran migrant left her home in hopes of finding work in the United States. She wanted to be able to afford surgery and costly medications for her ill 7-year-old daughter.
A Salvadoran migrant hangs off the back of a cargo train in Arriaga, Mexico, in July 2010.
Railroad tracks in Del Rio, Texas, in January 2004.
Central American migrants scramble to board a cargo train in Arriaga in January 2014.
Shadows deepen on hills as the sun begins to set during a 13-hour train ride carrying migrants from Arriaga to Ixtepec.
A Honduran migrant rests at an Arriaga shelter in June 2009.
Weary and injured migrants rest in the makeshift chapel of an Ixtepec shelter in June 2009.
A Guatemalan migrant and her 6-month-old baby.
Migrants ride a northbound freight train through the southern Mexican state of Oaxaca in July 2010.
Migrants rest in the shade of a mesquite tree in May 2012.
The Tijuana-San Diego border fence, as seen from the Mexican side of the border in August 2012.
A tunnel used by U.S. Border Patrol agents near the Arizona-Mexico border.
A Guatemalan couple in June 2009.