The question of precisely how far parliament should be involved in settling the succession to the crown constitutes a neglected strand of the Elizabethan succession debate. Patrick Collinson and his successors have examined in detail the attempts undertaken by committed Protestants from the 1560s through to the 1580s to secure legislation debarring Mary, queen of Scots. However, this chapter demonstrates that a necessary corollary of the campaign for exclusion was the argument that parliament, even one summoned after Elizabeth’s death without statutory warrant, could determine the identity of her rightful successor or even choose the next ruler. Theoretical justifications of this scenario, however, were seldom disinterested, and were typically designed with a practical purpose and a specific person in mind. It may be a mistake to treat them as expressions of abstract political thought. Drawing on new archival evidence, this chapter reveals that he intended beneficiary of the boldest such scheme propounded in 1586, when the Scottish queen was still alive, was her infant son James. It concludes by reflecting on the memory and polemical uses of Elizabethan parliaments in late Stuart England.