In criminology, subcultural theory emerged from the work of the Chicago School on gangs and developed through the symbolic interactionism school into a set of theories arguing that certain groups or subcultures in society have values and attitudes that are conducive to crime and violence. The primary focus is on juvenile delinquency because theorists believe that if this pattern of offending can be understood and controlled, it will break the transition from teenage offender into habitual criminal. Some of the theories are functionalist, assuming that criminal activity is motivated by economic needs, while others posit a social class rationale for deviance. Frederic M. Thrasher Frederic M. Thrasher (1927: 46) studied gangs in a systematic way, analyzing gang activity and behavior. He defined gangs by the process they go through to form a group: "The gang is an interstitial group originally formed spontaneously, and then integrated through conflict. It is characterized by the following types of behavior: meeting face to face, milling, movement through space as a unit, conflict, and planning. The result of this collective behavior is the development of tradition, unreflective internal structure, esprit de corps, solidarity, morale, group awareness, and attachment to a local territory." E. Franklin Frazier In the earliest stages of the Chicago School and their investigation of human ecology, one of the key tropes was the concept of disorganization which contributed to the emergence of an underclass. Albert K. Cohen Albert K. Cohen (1955) did not look at the economically oriented career criminal, but looked at the delinquency subculture, focusing on gang delinquency among working class youth in slum areas which developed a distinctive culture as a response to their perceived lack of economic and social opportunity within U.S. society. Richard Cloward and Lloyd Ohlin Richard Cloward and Lloyd Ohlin made reference to R. K. Merton's Strain Theory, while taking a further step in how the Subculture was 'Parallel' in their opportunities: the Criminal subculture had the same rules and level. Walter Miller Miller (1958, 1959) agreed with Cohen that there was a delinquency subculture, but argued that it arose entirely from the lower class way of life. David Matza David Matza (1964) argued that, rather than being committed to delinquency, young people drifted between conventional and unconventional behavior, thus due to - often - their unconventional childhood tribulations. Phil Cohen Phil Cohen (1972) studied the youth of East London in the early 1970s. He