This paper assesses the spatial concentration of employment at plant level in Italy between 2007 and 2021. We rely on a comprehensive data set including both manufacturing and service sectors at 3-digit ATECO. Our key measure of spatial concentration is theM function, which we analyze both at the aggregate and local level. In this way, we trace how the spatial concentration of economic activities has evolved across various geographic scales, while also keeping track of which local economies have contributed to such change.