This research note considers how to track long-term trajectories of political discontent in Britain. Many accounts are confined to using either survey data drawn from recent decades or imperfect behavioral measures such as voting or party membership as indicators of political disengagement. We instead develop an approach that provides the long view on political disaffection. We first consider time-series data available from repeated survey measures. We next replicate historic survey questions to observe change in public opinion relative to earlier points in time. Finally, we use Stimson's (1991) dyad-ratios algorithm to construct an over-time index of political discontent that combines data from multiple poll series. This reveals rising levels of political discontent for both specific and diffuse measures of mass opinion. Our method and findings offer insights into the rising tide of disillusionment afflicting many contemporary democracies.