Summary/AbstractStreet-seized crack cocaine samples are cut with diverse impurities which may be very harmful to health. Harm reduction experts say that interventions are urgently needed to reduce the harmful behaviours associated with drug abuse. In this multidisciplinary approach, a successful intervention, Promoting Inhaled Pleasure Easily and Safely (PIPES), has been designed and tested in pilot studies. PIPES informs crack smokers about the crack sample content, efficiency of crack delivery, and the harms associated with different home-made smoking tools and cutting agents.Crack samples were profiled by spectroscopic and chromatographic methods. In an attempt to track crack sources, PCA of the 1H NMR spectroscopic data clustered samples of similar contents together. A laboratory crack smoking model was optimised to measure the emitted and recovered doses of cocaine and cutting agents from common crack smoking devices. Seized samples contained 24% cocaine base and 32% phenacetin. A medical inhaler delivered the highest dose of cocaine and phenacetin into the apparatus, then a glass pipe (shooter), and then tin cans.The analytical results and the harms associated with each smoking device and toxic phenacetin were used to design PIPES, an educational intervention that was delivered by harm reduction workers to crack smokers. Users showed: a lack of knowledge of cutting agents and the harms associated with different pipes and cutting agents, their reasons for sharing pipes, and their attitudes to share knowledge and receive more information about cutting agents and pipes. The results of this applied research should be more widely known and used.