Sales Tax Act of 1990 also provides for mechanism of Withholding. Vide SRO No. 660(1)/2007 dated 30th June 2007 special procedure under the title of Sales Tax special procedure (Withholding Tax) Rules 2007, was introduced. Though within the Sales Tax structure share of Withholding Tax is quite minor and its scope is limited only to five types of Withholding Agents. But still there is further room for broadening its base.