c0c46a51_e___A_Summary_of_Design_Issues__Solutions
[Challenges] Frames cannot be "seen" all at once. They must be accessed separately, leading to disorientation. [Solutions] 
Don't use frames unless you have to. If you use them, provide frame titles that communicate their purpose (e.g. "navigational frame", "main content").
WebAIM: Considering the User Perspective - A Summary of Design Issues
Solutions