“…The authors have led several extended research projects examining the natural history of major drug eras in the New York City (NYC) metropolitan area including expansion of the Marijuana Era in the 1960s and 1970s (Johnson, 1973), Heroin Injection (Johnson et al, 1985;Johnson and Golub, 2002), Crack (Johnson et al, 1995), Crack distribution (Johnson et al, 2000), and recently Marijuana/Blunts (Golub, 2005;Golub and Johnson, 2006a,b;,Ream et al, 2006. They have recruited a wide variety drug users and identified drug abuse patterns among arrestees and criminals (Golub and Johnson, 1997,2004,2005,2006bJohnson et al, 2006b), impacts of policing upon arrestees (Golub et al, 2003, an analysis of new drug detection technologies (Liberty et al, 2004), estimating hard drug users and sellers (Davis and Johnson, 2000;Davis et al, 2003), an indepth analysis of violence among crack abuser households (Dunlap et al, 1996;Dunlap et al, 2003a,b), and other projects. A variety of research projects have documented similar patterns of illegal distribution in other societies, including Britain (Parker 2000), Italy (Ruggiero 2000), and other western countries (Natarajan and Hough 2000).…”