This book presents three related empirical studies on the performance and the long and short run dynamics between screened investment represented by Kuala Lumpur Syariah index (KLSI) and non-screened investment represented by Kuala Lumpur Composite index (KLCI) in Bursa Malaysia. The KLCI contains the largest 100 companies in Malaysia. This index facilitates as a barometer of the Malaysian economy while, the KLSI is the first Islamically compliant index in Bursa Malaysia. KLSI represents companies abiding to Islamic laws of transactions, which is determined by the scholars in the Syariah supervisory board employed by Bursa Malaysia. The KLCI represents the non-screened, which started with 400 companies in 1999 and reached 900 by 2007, common shares while KLSI represents the screened common shares in Bursa Malaysia.