A psychologist is someone who studies mental processes and human behavior by observing, interpreting, and recording how people relate to one another and the environment. Some psychologists work independently, doing research or working only with patients or clients. Others work as part of a healthcare team, collaborating with physicians, social workers, and others to treat illness and promote overall wellness.

The global psychologists market was valued at USD 39.8 billion in 2017. North America was the largest geographic region accounting for USD 19.1 billion or 0.4% of the global market. And the USA was the largest country accounting for USD 15.9 billion or 0.4% of the global psychologist market.

Increased use of online therapy and wellness-based mobile applications has lead the field of mental health to follow the path of physical health initiatives, in the design of more accessible and convenient platforms. This is called virtual mental health treatment. Online programs, such as MassMen.org, allow users to remain anonymous, a feature that was not possible before. This may encourage those less likely to seek help to address their mental health concerns.