Strategy: Types are the basis of re-use and not elements.

Make all your types (complex & simple) global.

The only except might be for elements that are lists of a single type/element.

The global elements should be:

• Document elements.

• Substitution group elements.

• Major components.

• "Utility" elements (e.g. links, math, etc.)

All other elements should be declared locally--typically with a global type.