This book strives to contribute to the research on private equity's portfolio capabilities by quantitatively analysing the hypothesis: Will portfolio performance be improved with respect to risk and return, when private equity is added to an investment portfolio consisting of stocks and bonds? Over the last decades, private equity has received substantial attention in the media, investment universe, and academic literature. This is with good reason, when considering the amount of capital committed to this asset class. However, it seems that mixed opinions exists with regards to whether these vast amounts of capital raised for this asset class has been justifiable. By justifiable is implied whether private equity investors are compensated for the extra risk associated with investing in this asset class.