These criminal syndicates are characteristzed by violence, organizational structure, camaraderie, discipline, and illegal activities. Modern boryokudan trends include monopolizing, internationalization, warring, racketeering, and solidifying. These organizations provide entertainment sources that allow the Japanese to divert the frustration and stress they experience due to their society's rigid social structure. The pachinko parlors, gambling houses, illegal drugs, lurid entertainment, and sex industry help alleviate some of the pressure and strain of daily life. The boryokudan also keep order in the areas that they control, maintaining strict order around their gambling institutions and houses of prostitutions. The police allow their activities to function in certain areas, talking no official action as long as the activities do not violate cultural taboos. However, when boryokudan gangs engage in unacceptable activities such as gun battles that injure innocent civilians, the police experience increased public pressure to enforce the laws vigorously. Further research should focus on the relaitonship between boryokudan drug trafficking, juvenile delinquency, and school disciplinary problems and the symbiotic relationship between boryokudan gangs, and police, and Japanese society. Cross-cultural studies are also needed. Figures and 162 references (Author abstract modified)