The authors describe the methods of pharmaceutical and criminalistics analysis that are finding the increasingly wider application for the drug expertise (identification) and elucidation of the circumstances conducive to the commission of an offence. The special emphasis is laid on the buprenorphine studies with the use of the colour chemical reactions, thin-layer chromatography, gas chromatographic analysis, high-performance liquid chromatography, IR spectrometry, and other modern techniques. The methods based on the recent achievements in pharmaceutical and criminalistics sciences can be employed in the activities intended to control the illegal drug circulation. Moreover, they may be of importance for obtaining valuable information about the actions of the persons involved in the trafficking or synthesis (production) of the prohibited substances after they are brought to criminal responsibility and/or appear before the court.