Urban Flow is a view of the cool urban culture that messengers have grown on the barren soil of the service economy, and reverberates with cycling's visceral pleasure.(American Journal of Sociology) Urban Flow's principle contribution is a call to sociologists of culture to more thoroughly examine emotions, space, and the relationship between the two; emotions are emplaced, and physical structures significantly shape interaction. Through what Kidder calls the 'affective appropriation of space' messengers resist the conformist, rationalized world of the city, affording moments, however small, of creativity and liberation.- Ross Haenfler (Qualitative Sociology)