Amid growing evidence that national occupational change trends mask substantial subnational heterogeneity, the author uses census data to visualize how the occupational structure changed within the 33 London borough between 1991 and 2021. The visualization documents a tale of two cities. The story in Inner London is one of clear upgrading: the proportion of residents employed in high-paying occupations increased by approximately 20 percentage points, while the proportion of residents employed in low- and midpaying occupations decreased markedly. In Outer London, the story is rather one of occupational polarization. Although the proportion of residents employed in high-paying jobs increased by 10 percentage points, the rate of growth was much slower, and growth at the top was generally accompanied by an increase in employment in low-paying jobs. These findings have important implications for the socioeconomic composition of schools, income inequality dynamics in London boroughs and potentially also for inequality beliefs and political behavior.