Eugene T. Kingsley led an extraordinary life. Born in mid-nineteenth-century New York, in 1890 he was a railway brakeman in Montana. An accident left him a double amputee and politically radicalized, and his socialist activism that followed took him north of the border where he eventually was considered by the government to be 'one of the most dangerous men in Canada'. Able to Leadtraces Kingsley's political journey, starting with his time as a soapbox speaker in San Francisco. As a leading member of the California left, he ran for the US House of Representatives. After moving to British Columbia, he rose to prominence in the Socialist Party of Canada and edited its newspaper, the Western Clarion. Although never elected to political office, Kingsley shaped an entire generation of Canadian leftists. Ravi Malhotra and Benjamin Isitt illuminate a figure who wielded considerable influence in an era when it was uncommon for disabled men to lead. They examine Kingsley's endeavours for justice against the Northern Pacific Railway, and how Kingsley's life intersected with immigration law and free-speech rights. Able to Lead brings a turbulent period in North American history to life, highlighting the implications of this profound legacy for the twenty-first-century political left.