Employment dynamics have a direct effect on health insurance coverage because most people obtain their health insurance through their workplace. In 2002-04, about three-fourths (441,000 people) of working-age Coloradans (age 18-64) who were uninsured reported working at some point during the previous calendar year. Who are the working uninsured? In what industries do they work, and for how long? This supplement to CHI’s Profile of the Uninsured in Colorado, 2004 examines the employment characteristics of uninsured workers. With some noted exceptions, the findings suggest that the uninsured working population is quite similar to insured workers.