Self-help or self-improvement is "a focus on self-guided, in contrast to professionally guided, efforts to cope with life problems" —economically, physically, intellectually, or emotionally—often with a substantial psychological basis.

When engaged in self-help, people often use publicly available information, or support groups—on the Internet as well as in person—in which people in similar situations work together. From early examples in pro se legal practice and home-spun advice, the connotations of the word have spread and often apply particularly to education, business, exercise, psychology, and psychotherapy, as commonly distributed through the popular genre of self-help books. According to the APA Dictionary of Psychology, potential benefits of self-help groups that professionals may not be able to provide include friendship, emotional support, experiential knowledge, identity, meaningful roles, and a sense of belonging.

Many different self-help group programs exist, each with its own focus, techniques, associated beliefs, proponents, and in some cases leaders. Concepts and terms originating in self-help culture and Twelve-Step culture, such as recovery, dysfunctional families, and codependency have become integrated into mainstream language.

Self-help groups associated with health conditions may consist of patients and caregivers. As well as featuring long-time members sharing experiences, these health groups can become support groups and clearinghouses for educational material. Those who help themselves by learning and identifying health problems can be said to exemplify self-help, while self-help groups can be seen more as peer-to-peer or mutual-support groups.

From classical antiquity, Hesiod's Works and Days is often considered an early example of moral and instructional literature. Scholars such as Lilah Grace Canevaro describe it as a poem teaching self-sufficiency, offering concrete advice on labor, justice, and moral conduct. It "opens with moral remonstrances, hammered home in every way that Hesiod can think of." The Stoics offered ethical advice "on the notion of eudaimonia—of well-being, welfare, flourishing."

The hyphenated compound word "self-help" often appeared in the 1800s in a legal context, referring to the doctrine that a party in a dispute has the right to use lawful means on their initiative to remedy a wrong.

Some consider the self-help movement to have been inaugurated by George Combe's Constitution (1828), which advocated personal responsibility and the possibility of naturally sanctioned self-improvement through education or proper self-control.

In 1841, an essay by Ralph Waldo Emerson, entitled Compensation, was published suggesting "every man in his lifetime needs to thank his faults" and "acquire habits of self-help" as "our strength grows out of our weakness." Samuel Smiles (1812–1904) published the first explicitly "self-help" book, titled Self-Help, in 1859. Its opening sentence: "Heaven helps those who help themselves", provides a variation of "God helps them that help themselves", the oft-quoted maxim that had also appeared previously in Benjamin Franklin's Poor Richard's Almanack (1733–1758).