The Development of Human Factors Psychology

Parallel to early work in industrial and organizational psychology, human factors psychology (also called ergonomics) was developing as researchers and engineers began asking a practical question:

How can we design work, tools, and systems to fit human abilities and limitations—so people can work safely and effectively?

Frederick Taylor and Scientific Management

Frederick Winslow Taylor was an engineer who believed workplaces could be redesigned to improve productivity. In 1911, he outlined his approach in The Principles of Scientific Management, emphasizing the use of systematic observation and time-and-motion studies to find the “one best way” to perform a task.

Taylor argued the following:

• The principal goal of management should be to make the most money for the employer, along with the best outcome for the employee.
• The best outcome for the employee and management would be achieved through training and development so that each employee could provide the best work.
• By conducting time and motion studies for both the organization and the employee, the best interests of both were addressed. Time-motion studies were methods aimed to improve work by dividing different types of operations into sections that could be measured. These analyses were used to standardize work and to check the efficiency of people and equipment.

His views on scientific management are sometimes called Taylorism, and he is still widely studied within the field of management.

Rest for Productivity

One of Taylor’s most famous demonstrations involved workers moving heavy iron ingots (“pig iron”). Taylor argued that productivity could improve if workers followed a carefully designed pattern of work and rest. Using this approach, productivity reportedly increased from 12.5 tons per day to 47.0 tons per day, while workers reported less fatigue and earned higher wages because they were paid by output. At the same time, the company’s cost dropped from 9.2 cents to 3.9 cents per ton.

Despite these increases in productivity, Taylor’s theory received a great deal of criticism at the time because it was believed that it would exploit workers and reduce the number of workers needed. Also controversial was the underlying concept that only a manager could determine the most efficient method of working, and that while at work, a worker was incapable of this.

Taylor’s theory was underpinned by the notion that a worker was fundamentally lazy and the goal of Taylor’s scientific management approach was to maximize productivity without much concern for worker well-being. His approach was criticized by unions and those sympathetic to workers (Van De Water, 1997).

The Gilbreths

Lillian Gilbreth (1878–1972) was another influential I-O psychologist who strove to find ways to increase productivity. Using time and motion studies, Gilbreth and her husband, Frank, worked to make workers more efficient by reducing the number of motions required to perform a task. She not only applied these methods to industry but also to the home, office, shops, and other areas. She investigated employee fatigue and time management stress and found many employees were motivated by money and job satisfaction.

In 1914, Gilbreth wrote the book title, The Psychology of Management: The Function of the Mind in Determining, Teaching, and Installing Methods of Least Waste, and she is known as the mother of modern management.

Some of Gilbreth’s contributions are still in use today: you can thank her for the idea to put shelves inside refrigerator doors, and she also came up with the concept of using a foot pedal to operate the lid of a trash can (Gilbreth, 1914, 1998; Koppes, 1997; Lancaster, 2004).

Gilbreth was the first woman to join the American Society of Mechanical Engineers in 1926, and in 1966 she was awarded the Hoover Medal of the American Society of Civil Engineers. And also, fun fact, the story and movie Cheaper by the Dozen was written by one of the twelve Gilbreth children about their life at home.

From Efficiency to “Fit”: Ergonomics and Human Factors

Taylor and the Gilbreths aimed to improve productivity, but their work also highlighted a deeper idea: technology and work systems should fit the human being using them.

That “machine–human fit” focus became central to human factors/ergonomics, which asks questions like:

• Is equipment designed in a way that matches human attention and memory limits?
• Does a workspace reduce strain and injury risk?
• Can people read displays quickly and accurately under pressure?

This is why human factors overlaps with areas like product design, safety engineering, usability testing, and workplace health.

I-O Psychology From WWII to Today

World War II greatly accelerated both industrial psychology and human factors research. As technology became more complex (aircraft systems, communication equipment, high-stakes decision environments), it became clear that safety and performance depended not only on selecting the “right” people—but also on designing systems around real human capabilities and limitations.

After WWII, research expanded in areas such as:

• job satisfaction and motivation
• training and performance appraisal
• fairness and bias in employment tests
• teamwork, morale, and leadership

In the U.S., the Civil Rights Act of 1964 (Title VII) pushed organizations to examine discrimination and improve hiring and promotion practices. This period helped shape I-O psychology’s long-standing emphasis on valid measurement and fair selection systems.

Human factors today: modern work, modern tools

Today, human factors work is especially visible in:

• remote and hybrid work ergonomics (workstation setup, fatigue, screen time)
• the design of digital tools (dashboards, alerts, interfaces)
• safety in high-risk fields (healthcare, transportation, manufacturing)
• newer questions about human–AI interaction, such as how automated recommendations affect attention, errors, and decision-making

The field today

I-O psychology is now a large, global field. The Society for Industrial and Organizational Psychology (SIOP) reports over 9,000 members worldwide. 

Today, I-O psychology is a diverse and deep field of research and practice, as you will learn about in the rest of this module. The Society for Industrial and Organizational Psychology (SIOP), a division of the APA, lists over 9,000 members (SIOP, 2022) and the Bureau of Labor Statistics—U.S. Department of Labor (2022) has projected a positive growth rate in the field and with an average salary of $105,000 in 2022.^[1]

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