CSS Accessibility

When designing a website using CSS, is it better to create external style sheets for each page? Or better to keep it all in the one external stylesheet??

For example: If I have a design layout for a website, I obviously use this one stylesheet throughout the site to keep continuity. But I tend to use internal styles on seperate pages, if the pages differ in format layout such as text and graphics.

Would it be betteror even more efficient to create an external sheet for each of these pages??

Deringer