Permanent establishment rules limit source taxation to profits attributable to a fixed place, guiding cross border business taxation. The Protocol revises residence and tie breaker rules, modernises the definition of permanent establishment including specified inclusions and exclusions and a six month rule for construction sites, and confines source taxation to profits attributable to a PE determined on an arm's length basis with allowed deductions for PE expenses. It also sets capped withholding rates and detailed rules for dividends, interest, royalties and technical fees, allocates capital taxation by situs or residence, and prescribes methods for elimination of double taxation and a mutual agreement procedure for resolving treaty application disputes.