XPath was introduced by the W3C as a standard language for specifying node selection, matching conditions, and for computing values from an XML document. XPath is now used in many XML standards such as XSLT or the forthcoming XQuery database access language. Since efficient XML content querying is crucial for the performance of almost all XML processing architectures, a growing need for studying high performance XPath-based querying has emerged. Our approach aims at optimizing XPath performance through static analysis and syntactic transformation of XPath expressions.