This chapter examines the general issue of leadership in the British political system and the stresses and strains of this task, examining the role of the prime minister. As well as being leader of the largest party in the House of Commons, able to command a majority, and potentially able to get government business through Parliament and into law, the prime minister has executive powers, which helps keep this focus. Despite the power of the position and its importance in the British system of government, there are fundamental weaknesses in the role that come from the instabilities of party politics. Overall, the picture of prime ministerial and core executive power and capacity is a mixed one that is changeable over time. In recent years, over Brexit and the Covid-19 pandemic, the prime minister's fate can change dramatically, even week-by-week.
