(Syringe Exchange Data And Trends For The Netherlands, 2012)
"• In Amsterdam, figures are available since 1990. After a steady increase until 1993 (1,082,880 syringes were exchanged in that year), the number of exchanged syringes declined and slightly fluctuates below 200,000 syringes per year since 2007 (146,000 in 2012) (source: M. Buster, GGD Amsterdam).

(High-Potency Cannabis and Titration of Dosage Among Experienced Users) "Although experienced young adult cannabis users with a preference for stronger joints titrated their THC exposure to some extent by inhaling less smoke, in general more potent cannabis was used in higher dosages leading to a higher THC exposure compared to users preferring lower potency cannabis.

(High-Potency Cannabis and Potential For Developing Dependence) "This study among 98 experienced cannabis smokers is the first naturalistic study to examine whether users of cannabis with high THC concentration titrate the psychoactive effects by using lower doses and/or by reduced inhalation, and whether cannabis smoking behaviour (topography) predicts cannabis dependence severity independently of total THC exposure.

(Smoking Behavior and Potential for Developing Dependence on Cannabis) "Differences in cannabis smoking behaviour may also represent different risks for cannabis dependence independently of total THC exposure. Similar to cigarette smokers [16,21–24], cannabis smokers typically gradually decrease the puff volume and puff duration during the course of one joint, whereas puff velocity and interpuff interval gradually increase [20].

(Comparison of Results from Standardized Field Sobriety Tests (SFST) and Roadside Saliva Drug Tests in Detecting Cannabis Use) "The SFST was mildly sensitive to the effects of cannabis alone. A dose of 400 ?g/kg body weight THC significantly increased the percentage of participants displaying impairments in OLS compared to baseline performance from 21 to 50 %. THC also increased percentage of individuals showing impairment on HGN from 0 to 15 %, relative to baseline, but this change only approached statistical significance.

(Comparison of Results from Standardized Field Sobriety Tests (SFST) and Roadside Drug Testing)
"Methods Twenty heavy cannabis users (15 males and 5 females; mean age, 24.3 years) participated in a double-blind, placebo-controlled study assessing percentage of impaired individuals on the SFST and the sensitivity of two oral fluid devices. Participants received alcohol doses or
alcohol placebo in combination with 400 ?g/kg body weight THC. We aimed to reach peak blood alcohol concentration values of 0.5 and 0.7 mg/mL.

(Changes In Cannabis Consumer Market Due To Changes In Dutch Coffee Shop Policies) "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).

(Personal Use Violations and Soft Drugs in Netherlands Criminal Law) "Police and Public Prosecutor give low priority to the investigation of possession of small amounts of a drug for own use. The Opium Act Directive of the Public Prosecutor state that, if the offence concerns possession of small amounts for own use of a hard drug, the drugs will be seized, but normally there will be no custody or prosecution. Diversion to care is the primary aim of custody or prosecution in cases of possession of hard drugs (Directive Opium Act 2011A021 2012, www.om.nl).

Crime, Courts, and Prisons

(Drug Offense Arrests in The Netherlands, 2011)
"• There is an increase in the total number of police reports of Opium Act offences in 2011.
"• There is an increase in both hard and soft drugs reports compared to 2010. The increase in soft drugs exceeds the increase in hard drugs offences. The number of reports of combinations of both hard and soft drugs has decreased. This type of cases forms a minority.

(Drug Consumption Rooms in The Netherlands, 2012) "The first formal drug consumption room in the Netherlands opened in 1994 and since the beginning of this century the number has rapidly increased. An inventory in 2010 among a network of infectious disease experts in all addiction care institutions in the Netherlands identified 37 drug consumption rooms, located in over 25 cities in the Netherlands (Havinga and Van der Poel 2012). In the last decade, due to several developments, the organisation of these locations and the population using them changed.