This paper explores as a case study the development of e-cigarette use and smoking within small friendship group (n=8) in Glasgow, Scotland. Interviewed twice at six months apart these 16/17 year olds reported substantial change in their use of and attitudes towards e-cigarettes and tobacco. At time 1 vaping generated much excitement and interest, with 6/8 having their own vape device. At time 2 only two young people still vaped, with the others no longer professing any interest in continued vaping. The two regular smokers, who had been smoking before they first vaped, now only vaped privately and to reduce their tobacco intake. This small case study illustrates plasticity in the use of electronic cigarettes; just as young people can initiate using these devices so too can they more away from their use- with such changes in actual use occurring within a relatively short period of time. These findings demonstrate more than anything else the volatility in young peoples’ substance use behaviour. If we are to better understand these behaviours we require both quantitative and qualitative research studies that are capable of both monitoring changes in individual and group behaviour over time but which are also able to elucidate the nuance of individual behaviour differentiating between long term, frequent, consistent use and more episodic, experimental and infrequent use by young people.