||Cheetah contains geographical, industry and accounting information on three cohorts of mid-sized firms that experienced fast growth (i.e., average annual sales or employment growth greater than 20% for at least three years) during three growth periods: 2008-2011, 2009-2012 and 2010-2013. Mid-sized firms are defined by combining the EUROSTAT definition of medium-sized firm and the French definition of Entreprise de Taille Intermédiaire (ETI). The uniqueness of this database lies in the focus on this category of firms and its coverage in terms of countries. Cheetah currently includes 42,369 mid-sized firms, which are located in 30 European countries and Israel. Services currently offered by the infrastructure: Cheetah is a brand new output of the first RISIS project. It is a unique source of data that offers to researchers new opportunities to study the growth dynamics of a relevant category of firms (i.e. mid-sized firms), which however has been almost neglected by the current academic literature on firm growth. The European dimension of Cheetah makes the data infrastructure well suited to address research questions concerning the institutional determinants of firm growth and geographical agglomeration effects.