Buy-and-build strategies (leveraged build-up, strategic roll-up) are part of the active portfolio management of private equity companies. Thereby the financial investors frequently focus on a certain fragmented industry. At first they conduct a buy-out of a larger company (so-called “platform investment”) and after that they purchase one or more smaller companies (so-called “add-on acquisitions”). The aim of the project is to analyse the European buy-and-build strategies, the influence of the private equity companies on the development and the value of the portfolio companies as well as the success factors for the acquisitions. Furthermore it is of interest to consider if private equity funds executing buy-and-build strategies achieve better rate of returns than funds without such strategies.