It is well known that immigrants make enormous contributions to the U.S. economy as workers, consumers, taxpayers, and entrepreneurs. As part of the labor force, immigrants are employed in a wide range of industries but tend to be concentrated in some occupations at both ends of the occupational spectrum. At the “lower end” of the scale, immigrants are overrepresented in occupations such as operators and laborers; service workers (e.g., service workers in private households; food preparation; and cleaning and building services); textiles and apparel; food production; and construction. The contributions of workers in these occupations are invaluable and the skills required to perform some of them can be challenging to acquire. However, because government statistical agencies and researchers simplistically classify those occupations as “low skill,” the abilities needed to perform these jobs—and the value of those jobs and of the workers that perform them—are routinely underestimated.

A recent report by sociologist Jacqueline Hagan sheds a new light on the often unappreciated value of the skills possessed by immigrant workers in some of these occupations. Specifically, she makes the case that skills encompass way more than just formal education:

“Expertise and abilities gained on the job, informally, or through specialized training programs can be adapted and used in a number of different settings. Yet, because skills are so often narrowly equated with level of education, the value of the work performed by low-wage workers (native-born and immigrant alike) is frequently devalued or overlooked entirely. From construction workers to gardeners, many low-wage immigrant workers are in fact quite skilled, but are frequently labeled as “less skilled” because their levels of formal educational attainment are relatively low or because the jobs they perform require little formal education.”

The author also shows that certain immigrant workers acquire a wide range of skills and abilities on the job in their home countries. Once in the United States, they transfer and apply those skills in their new jobs. Because technical, social, cultural, and interpersonal abilities are more difficult to measure than formal education and language skills, those harder-to measure-dimensions are usually not reflected in occupational classifications.

Take, for example, the case of Marco, a young migrant from Guanajuato, Mexico, who was interviewed by Hagan and her team of researchers for their study. Before migrating to the United States, Marco was employed as a chalan, an entry-level worker in the career line of an albañil, or skilled mason. In Mexico, the albañil is a craftsperson who is skilled in mixing brick materials and molding and laying bricks, all without any technologically advanced tools. Marco moved to North Carolina in 1990, when the housing and real-estate market was booming and consequently, the urban construction industry was experiencing rapid growth. He found a job as a construction worker where his tasks were initially limited to maintaining the construction site and assisting other construction workers. With time, however, Marco had the opportunity to demonstrate his plastering skills to his employer and learned framing and ceiling work from his co-workers. He, like many immigrant workers, was able to transfer his existing skill set to his U.S. job as well as learn new skills on the job. Today, Marco is a supervisor of a multi-million dollar condominium project in North Carolina.

To date, Hagan and her team have interviewed roughly 320 so-called “unskilled” migrants and former migrants in Mexico and the United States, as well as experts in immigrant-heavy U.S. industries such as construction and manufacturing, agriculture, retail and hospitality, and personal services. These cases reveal that many immigrant workers who are routinely classified as “unskilled” in fact possess highly specialized skills of great economic value to both their employers and the industries within which they work.

These findings take an especially important value in the current political context, characterized by misinformation, scapegoating, and an intentional demonization of immigrants. Today, millions of undocumented immigrant workers, who are critical to the health of some of these industries, are confronted with a painful uncertainty about their future. In more subtle ways, this uncertainty also clouds the future of these essential industries in which immigrants constitute a driving force.