A takeover announcement does not necessarily mean good news for stockholders of the acquiring firm. In fact, for a majority of takeovers it means losses in share prices. Motives that can explain this trend are agency and hubris. This thesis is an event study of 28 acquir-ing firms in Sweden between the years 1997-2005, and the purpose is set to see whether stock prices are affected or not. This has been done by the help of the market model. The empirical results show that the takeovers are on average value decreasing operations which indicate that agency and hubris are the primary motives even though one can not for cer-tain exclude synergy.