This paper explores the role of white box vs. black box testing. White box testing technologies have a definite but limited use and value. From a Web application security perspective it must be understood that significant blind spots come with white box testing. Ultimately white box testing is not sufficient to secure your applications: simply put organizations that rely solely on white box technologies will be exposed to vulnerabilities in their applications, thus making it an ineffectual method of testing real-world risks. This paper will demonstrate black box or dynamic testing is ultimately the appropriate solution for “truly” securing Web applications.