"Considerable changes have taken place on the cannabis consumer market in the south of the Netherlands between 1 May (the start of the enforcement of the B- and I-criteria) and October-November 2012:
"• Drug tourists mostly disappeared.
"• The number of visits to coffee shops decreased drastically (Nijkamp & Bieleman, 2013).
"• Cannabis users were purchasing their cannabis on the illegal market significantly more often. The cannabis users in the sample of the street survey purchased their cannabis less often from coffee shops and more often from mobile phone dealers, dealers selling from the street or buildings other than coffee shops and from or through friends (Korf, Benschop & Wouters, 2013).
"• The degree and frequency of the nuisance experienced by people living in the direct vicinity of coffee shops changed little, but there was a shift in the nature of the nuisance. Prior to 1 May 2012, local residents attributed the nuisance they experienced mostly to the coffee shops. After six months, the nature had shifted to nuisance due to drug dealing on the streets (Snippe & Bieleman, 2013). These changes became apparent quickly in the southern provinces after the implementation of the new criteria, but were not observed in the comparison group."

Source

Van Laar M.W., Cruts G, Van Ooyen-Houben M., Croes E., Van der Pol P., Meijer, R., Ketelaars T., (2014). The Netherlands drug situation 2013: report to the EMCDDA by the Reitox National Focal Point. Trimbos-instituut/WODC, Utrecht/Den Haag, p. 29.
http://www.emcdda.europa.eu/h…
http://www.emcdda.europa.eu/a…