The book of Acts is a missional text, containing many different missionary episodes and concepts. This work argues that Luke's primary purpose in writing Acts is to inspire and equip the church of his day for effective mission. It takes the form of a detailed linguistic and narrative analysis of key words, phrases, and missional passages in Acts. These are examined in the framework of four overlapping conceptual categories: missional stimuli, structures, strategies, and suffering. Acts' missional stimuli are the motivators and the power sources for mission. Acts' missional structures are the foundational physical and social building blocks for successful mission. Acts' missional strategies articulate how the worldwide mission of Jesus is to be carried out. Acts' missional suffering is practical instruction about how to respond to persecution and imprisonment when a missionary experiences it. Luke expresses all of these, with the goal of calling the church to missional action, that his readers might be Christ's witnesses, even to the ends of the earth.