How should we best characterise the UK party system in the wake of nearly a decade and a half of Conservative government? Has it undergone a significant and enduring realignment, or merely amounted to passing turbulence, after which things have returned to the seemingly eternal verities of stable two-party competition? The question for us to consider in this chapter is whether we can regard the period since 2010 in such terms: in particular, does the general election of December 2019 constitute a moment of critical realignment? Or is it more sensible to view this as the mere culmination of a relatively prolonged period of Conservative Party ascendancy based on a regular swing of the electoral pendulum – a swing which will inevitably reverse itself as the centre of electoral gravity shifts in favour of Labour once more? In other words, a simple affirmation of the age-old dynamics of the two-party system.