BOSTON — Imagine if every worker in the United States drifted around the country each morning in search of temporary employment, not knowing if, or when, they would be paid a few dollars for a long day of labor.

Now add 50 million people to that unstable, wandering mass and you'd have what's been happening inside China for decades.

As many as 200 million migrant workers flow through the country, often traveling thousands of miles from their homes in rural areas to fill factories, construction sites and street markets, performing a variety of strenuous, tedious and sometimes dangerous jobs.

These workers are part of the largest migration in human history, and have helped power an economy that has grown more than tenfold the past 30 years.

Despite their importance to China's rising might, most migrants lead tenuous lives without proper access to health care, education and other social services. It's an existence that's been made even more fragile by the global economic crisis.

While conditions inside China have improved in recent months — a relieved Chinese government says migrants have been returning to work at a rapid rate — life remains difficult. Twenty million lost their jobs when Chinese exports collapsed last year, and many migrants were forced to travel back to poor villages that were ill-equipped to handle their return.

At the height of the crisis, GlobalPost contributing photographer Sharron Lovell and producer David Campbell documented the lives of three workers in Shanghai, the country's commercial capital.

This multimedia report Living in the Shadows is an intimate and powerful portrait of these challenging and often desperate lives.

And for the backstory, it includes recent GlobalPost coverage from correspondents Kathleen E. McLaughlin and Josh Chin, as well as analysis from yours truly on a variety of topics — from China's troubled health care system, to Beijing's digital dilemma, to its rising political and economic prominence on the world stage, to the spending habits of its young, dynamic, and sometimes restive population.

(Editor's note: For her initial research and reporting on China's migrant workers, Sharron Lovell received a generous grant from LSE Global Governance.)

http://www.globalpost.com/dispatch/commerce/090910/china-economy-migrant-workers-economic-crisis