CRAVING place in ICD-10 (WHO, 1992) as one of the diagnostic criteria for dependence wherein it has been referred as "a strong desire or compulsion" to use the drug. The understanding of the term craving should include an inquiry in to the phenomena as described by substance users. A comprehensive description of the subjective experience of craving would lead to a better understanding of this term. Few researchers have attempted to study this. A recent study (Merikle, 1999) has explored the subjective experience of craving and has also reviewed the earlier studies which attempted this. It was revealed that the subjective experience of craving was heterogeneous. Eight dimensions: specificity, strength, positive outcomes, behavioral intentions, thoughts, physical symptoms, affects and cues, were associated with craving. The aim of the present study is to collect detailed information of the subjective experience of craving as described by the heroin dependent subjects in our setting. MATERIAL AND METHODS This study included 30 male subjects of heroin dependence syndrome diagnosed according to DSM-IV (APA, 1994) and attending the Drug Dependence Treatment Centre, All India Institute of medical Sciences, New Delhi. All subjects were interviewed with a semi-structured questionnaire. The questions included in the questionnaire pertained to demographic data, history related to heroin use, the subjective experience of craving and dimensions of craving, (specificity in relation to substance used, intensity, expected effects of drug use, intention to use drug, thoughts/cognitions associated with craving, physical symptoms related to craving, affect and cues that trigger craving). Some of the questions were open-ended. Subjects were asked questions on intensity of craving produced by a particular cue and responses were taken on the visual analogue scale. The questionnaire was formulated by a team of three drug dependence treatment specialists. The questionnaire was administered in the local language. The instrument was administered to four subjects and suitable modifications were made based on their feedback. RESULTS Subjects had a mean age of 35.5±5.8 years (range 27-54 years) and a mean duration of heroin use of 13.9±5.4 years (range 3-22 years). Definition: All subjects reported having experienced craving at sometime in their drug use history. Twentyseven subjects (90%) described craving as a strong desire to use the substance. Some subjects reported tension in mind (6.7%), restlessness (6.7%) and inability to remain without drug (6.7%) as components of craving. Almost all the subjects perceived that craving was uncontrollable. Majority of subjects (66.7%) reported that craving and withdrawal symptoms were different while 33.3% considered the two to be same. Fifty percent of subjects clearly described craving as a desire for the drug and withdrawal symptoms as a physical experience. Specificity: Eight subjects (26.7%) reported that only heroin would satisfy the craving while another 17 subjects (56.7%) stated that besides heroin, other opiates (opium, buprenorphine or dextropropoxyphene) could also relieve craving. Other substances like benzodiazepine (23.3%), alcohol (13.3%) and cannabis (10%) would also satisfy craving to some extent. Activities like taking a bath (10%) and talking (3.3%) had also been found helpful in reducing craving. Intensity: Majority of subjects (76.7%) reported that the intensity of craving could vary whereas remaining 33.3% experienced the intensity of craving to be the same every time i.e., always strong. Strong craving was described as uncontrollable and always leading to use of the substance. Overall 76.7% of subjects tried to control craving at some point of time. However, they were able to do so only on a few occasions. Subjects reported that frequency of craving decreased as the length of abstinence increased. Majority of subjects (76.7%) were experiencing craving 2-3 times or more a day while they were 139 (