Left-libertarianism comes in two main varieties: equal share and equal opportunity for well-being. Although equal share left-libertarians have supported a basic income guarantee, its equal opportunity counterparts either ignore a basic income in their theorizing or reject it. This article offers four reasons why left-libertarians should consider a basic income as a way to promote equality of opportunity for well-being: a basic income enhances self-respect, a basic income opens up the possibility of personal projects beyond traditional employment, a basic income (...) protects negative freedom, and a basic income minimizes potential for abuses and mistakes of centralized authorities. Peter Vallentyne’s objection to basic income is also considered. His asset-oriented account of the Lockean proviso is rejected in favor of an equality-promoting account that requires a substantial basic income. (shrink)