This essay offers an account of feasible actions. It criticizes the conditionalaccount of feasibility and offers instead what I call the constrained account offeasibility. The constrained account is superior, I argue, on account of how itdeals with the problem of motivational failure to act and with collectiveaction. According to the constrained account, roughly put, an action is feasiblewhen the agent or agents performing it know how to perform it and areappropriately responsive to incentives. The essay shows that some collectiverequirements for action that appear feasible are not in fact feasible.