To move beyond current aggregate and static conclusions regarding radicalisation and subsequent terrorist behaviour, empirical research should look to criminological models which are influenced by the life-course perspective. Current UK government policy designed to prevent radicalisation and terrorist engagement look to outputs from criminological perspectives to inform policy and practice. However, the guidance suffers from a lack of specificity as to the major concept of ‘vulnerability to radicalisation’, and what this incorporates. This investigation uses sequential analyses to add to our understanding of ‘vulnerability’ in the specific context of lone-actor terrorism. The statistical method bridges the gap between qualitative and quantitative approaches and provides a series of empirical outputs which visualise typical lone-actor terrorist trajectories through the discrete stages of radicalisation, attack planning and attack commission.