Electronic cigarettes (e-cigarettes) are subject to considerable public health debate. Most public health experts agree that for smokers who find it particularly challenging to quit, e-cigarettes may reduce harm. E-cigarette use in the home may also reduce children's secondhand smoke (SHS) exposure, although e-cigarette vapour may pose risks. This is the first qualitative study to explore disadvantaged parents' views and experiences of e-cigarettes in relation to reducing SHS exposure in the home. Interviews with 25 disadvantaged parents from Edinburgh who smoked and had children aged 1-3 were conducted in 2013, with 17 re-interviewed in 2014. Accounts of e-cigarette perceptions and use were analysed thematically. E-cigarettes were seen by some as potentially valuable in helping quitting or reducing smoking in difficult circumstances, and protecting children from SHS when smoking outside is constrained. However, parents raised concerns about safety issues and continuing their nicotine addiction. In relation to children, concerns included possible health effects of the vapour, children playing with them and role-modelling e-cigarette use. While significant concerns remain about e-cigarettes, for some parents who find it challenging to quit or safely leave their children to smoke outside, e-cigarettes may offer potential for reducing the harm to them and their children.