With the “candlelight revolution,” Koreans have elevated their democracy to another level. But the challenge they face is formidable. The protesters were calling for more than just the ousting of an errant president and her cronies: They want to create a cleaner and fairer society.

The most immediate challenge Koreans face is that of ridding the political system of corruption. Illicit dealings among politicians, high-ranking officials and chaebols — family-controlled business empires — are common. This August, Lee Jae-yong, the de facto head of Samsung, one of the most prominent chaebols, was sentenced to five years in prison for bribing Park and her notorious confidante Choi Soon-sil.

Some believe that corruption can be eliminated by further deregulation, with the idea that this would reduce the number of opportunities for collusion with public officials, and by strengthening minority shareholder rights, on the theory that shareholders will expose corrupt dealings by those who run the chaebols. However, a much more fundamental shift in the distribution of power is required if there is to be a reduction in corruption. Decision-making abilities need to be transferred from the political and business elites to citizens, civic organizations, trade unions and other “countervailing powers,” to borrow an expression from the economist John Kenneth Galbraith.

Then there is the issue of fairness. Increasing deregulation has reduced protections for small factories and shops, which used to supply jobs that kept income inequality relatively low. The spread of American-style salary norms in the past decade or so has led to a tremendous increase in wage inequality — South Korea has one of the fastest-growing levels among the countries in the Organization for Economic Cooperation and Development.

But what angers South Koreans most is the marked drop in social mobility and the sense of hopelessness that haunts young people from less-privileged backgrounds — that is, most young people.

This lack of social mobility is sometimes the result of blatantly corrupt practices. Of all the corruption scandals the former president faces, particularly upsetting for many was the accusation that Ms. Choi influenced Ewha Womans University in Seoul, one of the nation’s leading universities, to accept Ms. Choi’s daughter at the expense of candidates who were better qualified.

The barriers to university applicants are usually subtle. It’s the extras that make a candidate for admission stand out, such as extracurricular activities or expensive private tutoring for university entrance exams. At the beginning of their careers, expectations that candidates have completed internships may stand in the way. Poor parents cannot even dream of helping their children with such things.