Spain is debating reforming its current property tax system, known as the IUSI. The central argument gaining support advocates for taxing the value of land itself, rather than the buildings constructed upon it. Proponents believe this shift would disincentivize land speculation, encouraging more efficient land use and potentially lowering housing costs. Taxing land value is seen as capturing unearned gains from land appreciation, addressing wealth inequality. Furthermore, it could stimulate construction and development as land holding becomes less profitable without improvements. This approach is also considered more economically efficient, as it doesn’t penalize improvements to property. The reform aims to address concerns surrounding the current system’s focus on structures, which can discourage investment in building maintenance and renovation.