Taiwan Securities industry is dealing with not only internal competitors but more global companies which have much stronger competitiveness in terms of size, people and products after joining WTO, signing ECFA and cross-strait MOU, as well as government providing looser regulations against financial market. To complete with coming stronger competitors, Taiwan securities companies need to become bigger by M&A, which would be the trend in the future. I will take the M&A case of Yuanta/Polaris as a case study to discuss the motivation, strategic consideration and valuation as well as how to chose the ideal target to maximum synergy while making a M&A deal.